Greenlight

The Security Tango

What is the Security Tango?

The Security Tango is my name for the dance you have to do every time you want to assure yourself that your computer is free of viruses, spyware, keystroke loggers, backdoors, trojans, and other forms of malware (click the Definitions button in the menu to see what all those things mean). It's something you need to do regularly and often - daily is not too often! The simple act of getting on the Internet and downloading email or going to a Web page can expose your computer to malicious crackers who would love to take over your machine for their own use.

Let's Dance!

To dance the Security Tango, click the Let's Dance link up above.

Two left feet? Don't worry - it's not as hard as you might think!

Which Operating System Do You Use?

Originally, the Security Tango was mostly for Windows-based computers. I'm sure that those of you running Linux or a Macintosh used to laugh yourselves sick at all the machinations that your Windows-using friends had to go through to keep themselves safe. But don't get too complacent - your time is here! As Linux and the Mac have become more popular, we've see more viruses for them. Yes, there are verified malware programs out there for both the Macintosh and for Linux. You need to protect yourself. Equally importantly, if you don't at least run an antivirus program, you run the risk of passing a virus on to your Windows friends (assuming any of them actually talk to you). And that's just not being a good net citizen!

So I've split the Tango into three parts - one for Windows, one for Linux, and one for the Macintosh. But you get to all of them by that same "Let's Dance!" button in the menu!

Latest Virus Alerts


TA15-120A: Securing End-to-End Communications

Original release date: April 30, 2015

Systems Affected

Networked systems

Overview

Securing end-to-end communications plays an important role in protecting privacy and preventing some forms of man-in-the-middle (MITM) attacks. Recently, researchers described a MITM attack used to inject code, causing unsecured web browsers around the world to become unwitting participants in a distributed denial-of-service attack. That same code can be employed to deliver an exploit for a particular vulnerability or to take other arbitrary actions.

Description

A MITM attack occurs when a third party inserts itself between the communications of a client and a server. MITM attacks as a general class are not new. Classic MITM attacks (e.g., ARP Spoofing) focus on redirecting network communications. By definition, network infrastructure under attacker control is vulnerable to MITM. However, as technology evolves, new methods for performing MITM attacks evolve as well.

Currently, there is no single technology or configuration to prevent all MITM attacks. However, increasing the complexity with multiple layers of defense may raise the cost for the attacker. Increasing the attacker’s cost in time, effort, or money can be an effective deterrent to avoiding future network compromise.

Generally, encryption and digital certificates provide an effective safeguard against MITM attacks, assuring both the confidentiality and integrity of communications. As a result, modern MITM attacks have focused on taking advantage of weaknesses in the cryptographic infrastructure (e.g., certificate authorities (CAs), web browser certificate stores) or the encryption algorithms and protocols themselves.

Impact

MITM attacks are critical because of the wide range of potential impacts—these include the exposure of sensitive information, modification of trusted data, and injection of data.

Solution

Employing multiple network and browser protection methods forces an attacker to develop different tactics, techniques, and procedures to circumvent the new security configuration.

US-CERT recommends reviewing the following mitigations to reduce vulnerability to MITM attacks:

Update Transport Layer Security and Secure Socket Layer (TLS/SSL)

US-CERT recommends upgrading TLS to 1.1 or higher and ensuring TLS 1.0 and SSL 1, 2, 3.x are disabled, unless required. TLS 1.0 clients can fall back to version 3.0 of the SSL protocol, which is vulnerable to a padding oracle attack when Cypher-Block Chaining mode is used. This method is commonly referred to as the "POODLE" (Padding Oracle on Downgraded Legacy Encryption) attack. Vulnerable TLS implementations can be updated by applying the patch provided by the vendor. Vendor information is available in the National Vulnerability Database (NVD) entry for CVE-2014-3566 [1] or in CERT Vulnerability Note VU#577193 [2]. See US-CERT TA14-290A [3] for additional information on this vulnerability.

Utilize Certificate Pinning

Certificate pinning [4] is a method of associating X.509 certificate and its public key to a specific CA or root. Typically, certificates are validated by checking a verifiable chain of trust back to a trusted root certificate. Certificate pinning bypasses this validation process and allows the user to trust “this certificate only” or “trust only certificates signed by this certificate.” Please use the following resources to configure your browser for certificate pinning:

Microsoft Certificate Trust

The Microsoft Enhanced Mitigation Experience Toolkit (EMET) 5.2 employs a feature named "Certificate Trust" for SSL/TLS certificate pinning. This feature is intended to detect and stop MITM attacks that leverage Public Key Infrastructure. [5]

To use the Certificate Trust, you must provide a list of websites you want to protect and certificate pinning rules applicable to those websites. In order to do this, work with the Certificate Trust Configuration feature of the graphical application or use the Configuration Wizard to automatically configure EMET with the recommended settings. [6] Also, ensure period defaults are updated through patching.

Browser Certificate Pinning

Google Chrome and Mozilla Firefox, among others, perform certificate pinning. They conduct a variation of certificate pinning using the HTTP Strict Transport Security (HSTS), which pre-loads a specific set of public key hashes into the HSTS configuration, limiting valid certificates to only those with the specified indicated public key. Chrome uses HTTPS pins for most Google properties. It uses whitelisted public keys which include keys from Verisign, Google Internet Authority, Equifax, and GeoTrust. Thus, Chrome will not accept certificates for Google properties from other CAs.

Firefox 32 on desktop and later (Firefox 34 and later on Android) has the ability to use certificate pinning. It also has the ability to enforce built-in pinsets (mapping of public keys) information to domains. Firefox will pin all sites that Chrome already does, pin their own sites after audit and cleansing, and pin other popular sites that are already in good standing. Please visit this site on How to Use Pinning [7] and for more information.

Implement DNS-based Authentication of Named Entities (DANE)

DANE is a protocol that allows certificates (X.509) commonly used for TLS. DANE is bound to DNS which uses Domain Name System Security Extensions (DNSSEC). A working group in the Internet Engineering Task Force of DANE developed a new type of DNS record that allows a domain itself to sign statements about which entities are authorized to represent it. [8]

Google Chrome does not use DANE but uses an add-on [9] for support. Mozilla Firefox also uses an add-on [10] to check the existence and validity of DNSSEC.

Use Network Notary Servers

Network notary servers aim to improve the security of communications between computers and websites by enabling browsers to verify website authenticity without relying on CAs. CAs are often considered a security risk because they can be compromised. [11] As a result, browsers can deem fraudulent sites trustworthy and are left vulnerable to MITM attacks.

Each network notary server, or group of servers, is public and can be operated by public/private organizations or individuals. These servers regularly monitor websites and build a history of each site’s certificate data over time. When a browser equipped with a network notary add-on communicates with a website and obtains its certificate information, a user-designated network notary server supplies the browser with historical certificate data for that site. If certificate information provided by the website is inconsistent with the notary’s historical data, a MITM attack could be at play. [12]

References

Revision History

  • April 30, 2015: Initial Release

This product is provided subject to this Notification and this Privacy & Use policy.



TA15-119A: Top 30 Targeted High Risk Vulnerabilities

Original release date: April 29, 2015 | Last revised: May 06, 2015

Systems Affected

Systems running unpatched software from Adobe, Microsoft, Oracle, or OpenSSL. 

Overview

Cyber threat actors continue to exploit unpatched software to conduct attacks against critical infrastructure organizations. As many as 85 percent of targeted attacks are preventable [1].

This Alert provides information on the 30 most commonly exploited vulnerabilities used in these attacks, along with prevention and mitigation recommendations.

It is based on analysis completed by the Canadian Cyber Incident Response Centre (CCIRC) and was developed in collaboration with our partners from Canada, New Zealand, the United Kingdom, and the Australian Cyber Security Centre.

Description

Unpatched vulnerabilities allow malicious actors entry points into a network. A set of vulnerabilities are consistently targeted in observed attacks.

Impact

A successful network intrusion can have severe impacts, particularly if the compromise becomes public and sensitive information is exposed. Possible impacts include:

  • Temporary or permanent loss of sensitive or proprietary information,
  • Disruption to regular operations,
  • Financial losses relating to restoring systems and files, and
  • Potential harm to an organization’s reputation.

Solution

Maintain up-to-date software

The attack vectors frequently used by malicious actors such as email attachments, compromised “watering hole” websites, and other tools often rely on taking advantage of unpatched vulnerabilities found in widely used software applications. Patching is the process of repairing vulnerabilities found in these software components.

It is necessary for all organizations to establish a strong ongoing patch management process to ensure the proper preventive measures are taken against potential threats. The longer a system remains unpatched, the longer it is vulnerable to being compromised. Once a patch has been publicly released, the underlying vulnerability can be reverse engineered by malicious actors in order to create an exploit. This process has been documented to take anywhere from 24-hours to four days. Timely patching is one of the lowest cost yet most effective steps an organization can take to minimize its exposure to the threats facing its network.

Patch commonly exploited vulnerabilities

Executives should ensure their organization’s information security professionals have patched the following software vulnerabilities. Please see patching information for version specifics.

Microsoft
CVEAffected ProductsPatching Information
CVE-2006-3227​Internet ExplorerMicrosoft Malware Protection Encyclopedia Entry
CVE-2008-2244Office WordMicrosoft Security Bulletin MS08-042
CVE-2009-3129Office
Office for Mac
Open XML File Format Converter for Mac
Office Excel Viewer
Excel
Office Compatibility Pack for Word, Excel, and PowerPoint
Microsoft Security Bulletin MS09-067
​CVE-2009-3674​Internet Explorer​Microsoft Security Bulletin MS09-072
CVE-2010-0806​​Internet ExplorerMicrosoft Security Bulletin MS10-018
CVE-2010-3333Office
Office for Mac
Open XML File Format Converter for Mac
Microsoft Security Bulletin MS10-087
CVE-2011-0101ExcelMicrosoft Security Bulletin MS11-021
CVE-2012-0158Office
SQL Server
BizTalk Server
Commerce Server
Visual FoxPro
Visual Basic
Microsoft Security Bulletin MS12-027
CVE-2012-1856Office
SQL Server
Commerce Server
Host Integration Server
Visual FoxPro Visual Basic
Microsoft Security Bulletin MS12-060
​CVE-2012-4792​Internet Explorer​Microsoft Security Bulletin MS13-008
CVE-2013-0074​Silverlight and Developer RuntimeMicrosoft Security Bulletin MS13-022
CVE-2013-1347​Internet ExplorerMicrosoft Security Bulletin MS13-038
CVE-2014-0322​​​Internet ExplorerMicrosoft Security Bulletin MS14-012
CVE-2014-1761Microsoft Word
Office Word Viewer
Office Compatibility Pack
Office for Mac
Word Automation Services on SharePoint Server
Office Web Apps
Office Web Apps Server
Microsoft Security Bulletin MS14-017
​CVE-2014-1776​Internet ExplorerMicrosoft Security Bulletin MS14-021
CVE-2014-4114​WindowsMicrosoft Security Bulletin MS14-060
Oracle
CVEAffected ProductsPatching Information
CVE-2012-1723Java Development Kit, SDK, and JREOracle Java SE Critical Patch Update Advisory - June 2012
CVE-2013-2465Java Development Kit and JREOracle Java SE Critical Patch Update Advisory - June 2013
Adobe
CVEAffected ProductsPatching Information
​CVE-2009-3953Reader Acrobat ​Adobe Security Bulletin APSB10-02​
​CVE-2010-0188​Reader AcrobatAdobe Security Bulletin APSB10-07
CVE-2010-2883Reader Acrobat ​Adobe Security Bulletin APSB10-21
CVE-2011-0611​Flash Player
AIR
Reader
Acrobat
Adobe Security Bulletin APSB11-07
Adobe Security Bulletin APSB11-08​
​CVE-2011-2462Reader Acrobat ​Adobe Security Bulletin APSB11-30
​CVE-2013-0625ColdFusion​Adobe Security Bulletin APSB13-03
CVE-2013-0632​ColdFusionAdobe Security Bulletin APSB13-03
​CVE-2013-2729​Reader AcrobatAdobe Security Bulletin APSB13-15
​CVE-2013-3336​ColdFusionAdobe Security Bulletin APSB13-13
CVE-2013-5326​ColdFusionAdobe Security Bulletin APSB13-27
CVE-2014-0564Flash Player
AIR
AIR SDK & Compiler
Adobe Security Bulletin APSB14-22
OpenSSL
CVEAffected ProductsPatching Information
CVE-2014-0160OpenSSLCERT Vulnerability Note VU#720951

 

Implement the following four mitigation strategies.

As part of a comprehensive security strategy, network administrators should implement the following four mitigation strategies, which can help prevent targeted cyber attacks.

RankingMitigation StrategyRationale
1Use application whitelisting to help prevent malicious software and unapproved programs from running.Application whitelisting is one of the best security strategies as it allows only specified programs to run, while blocking all others, including malicious software.
2Patch applications such as Java, PDF viewers, Flash, web browsers and Microsoft Office.Vulnerable applications and operating systems are the target of most attacks. Ensuring these are patched with the latest updates greatly reduces the number of exploitable entry points available to an attacker.
3Patch operating system vulnerabilities.
4Restrict administrative privileges to operating systems and applications based on user duties.Restricting these privileges may prevent malware from running or limit its capability to spread through the network.

It is recommended that users review US-CERT Security Tip (ST13-003) and CCIRC’s Mitigation Guidelines for Advanced Persistent Threats for additional background information and to assist in the detection of, response to, and recovery from malicious activity linked to advance persistent threats [2, 3].

 

References

Revision History

  • April 29, 2015: Initial release

This product is provided subject to this Notification and this Privacy & Use policy.



TA15-105A: Simda Botnet

Original release date: April 15, 2015

Systems Affected

Microsoft Windows

Overview

The Simda botnet – a network of computers infected with self-propagating malware – has compromised more than 770,000 computers worldwide [1].

The United States Department of Homeland Security (DHS), in collaboration with Interpol and the Federal Bureau of Investigation (FBI), has released this Technical Alert to provide further information about the Simda botnet, along with prevention and mitigation recommendations.

Description

Since 2009, cyber criminals have been targeting computers with unpatched software and compromising them with Simda malware [2]. This malware may re-route a user’s Internet traffic to websites under criminal control or can be used to install additional malware. 

The malicious actors control the network of compromised systems (botnet) through backdoors, giving them remote access to carry out additional attacks or to “sell” control of the botnet to other criminals [1]. The backdoors also morph their presence every few hours, allowing low anti-virus detection rates and the means for stealthy operation [3].    

Impact

A system infected with Simda may allow cyber criminals to harvest user credentials, including banking information; install additional malware; or cause other malicious attacks. The breadth of infected systems allows Simda operators flexibility to load custom features tailored to individual targets.

Solution

Users are recommended to take the following actions to remediate Simda infections:

  • Use and maintain anti-virus software - Anti-virus software recognizes and protects your computer against most known viruses. It is important to keep your anti-virus software up-to-date (see Understanding Anti-Virus Software for more information).
  • Change your passwords - Your original passwords may have been compromised during the infection, so you should change them (see Choosing and Protecting Passwords for more information).
  • Keep your operating system and application software up-to-date - Install software patches so that attackers cannot take advantage of known problems or vulnerabilities. Many operating systems offer automatic updates. If this option is available, you should enable it (see Understanding Patches for more information).
  • Use anti-malware tools - Using a legitimate program that identifies and removes malware can help eliminate an infection. Users can consider employing a remediation tool (examples below) that will help with the removal of Simda from your system.

          Kaspersky Lab : http://www.kaspersky.com/security-scan

          Microsoft: http://www.microsoft.com/security/scanner/en-us/default.aspx

          Trend Micro: http://housecall.trendmicro.com/

  • Check to see if your system is infected – The link below offers a simplified check for beginners and a manual check for experts.

          Cyber Defense Institute:  http://www.cyberdefense.jp/simda/

The above are examples only and do not constitute an exhaustive list. The U.S. government does not endorse or support any particular product or vendor.

References

Revision History

  • April 15, 2015: Initial Release

This product is provided subject to this Notification and this Privacy & Use policy.



TA15-103A: DNS Zone Transfer AXFR Requests May Leak Domain Information

Original release date: April 13, 2015 | Last revised: April 15, 2015

Systems Affected

Misconfigured Domain Name System (DNS) servers that respond to global Asynchronous Transfer Full Range (AXFR) requests.

Overview

A remote unauthenticated user may request a DNS zone transfer from a public-facing DNS server. If improperly configured, the DNS server may respond with information about the requested zone, revealing internal network structure and potentially sensitive information.

Description

AXFR is a protocol for “zone transfers” for replication of DNS data across multiple DNS servers. Unlike normal DNS queries that require the user to know some DNS information ahead of time, AXFR queries reveal resource records including subdomain names [1]. Because a zone transfer is a single query, it could be used by an adversary to efficiently obtain DNS data.  

A well-known problem with DNS is that zone transfer requests can disclose domain information; for example, see CVE-1999-0532 and a 2002 CERT/CC white paper [2][3]. However, the issue has regained attention due to recent Internet scans still showing a large number of misconfigured DNS servers. Open-source, tested scripts are now available to scan for the possible exposure, increasing the likelihood of exploitation [4].

Impact

A remote unauthenticated user may observe internal network structure, learning information useful for other directed attacks.

Solution

Configure your DNS server to respond only to zone transfer (AXFR) requests from known IP addresses. Many open-source resources give instructions on reconfiguring your DNS server. For example, see this AXFR article for information on testing and fixing the configuration of a BIND DNS server. US-CERT does not endorse or support any particular product or vendor.

References

Revision History

  • April 13, 2015: Initial Release

This product is provided subject to this Notification and this Privacy & Use policy.



TA15-098A: AAEH

Original release date: April 09, 2015

Systems Affected

  • Microsoft Windows 95, 98, Me, 2000, XP, Vista, 7, and 8
  • Microsoft Server 2003, Server 2008, Server 2008 R2, and Server 2012

Overview

AAEH is a family of polymorphic downloaders created with the primary purpose of downloading other malware, including password stealers, rootkits, fake antivirus, and ransomware.

The United States Department of Homeland Security (DHS), in collaboration with Europol, the Federal Bureau of Investigation (FBI) and the Department of Justice (DOJ), released this Technical Alert to provide further information about the AAEH botnet, along with prevention and mitigation recommendations.

Description

AAEH is often propagated across networks, removable drives (USB/CD/DVD), and through ZIP and RAR archive files. Also known as VObfus, VBObfus, Beebone or Changeup, the polymorphic malware has the ability to change its form with every infection. AAEH is a polymorphic downloader with more than 2 million unique samples. Once installed, it morphs every few hours and rapidly spreads across the network.  AAEH has been used to download other malware families, such as Zeus, Cryptolocker, ZeroAccess, and Cutwail.

Impact

A system infected with AAEH may be employed to distribute malicious software, harvest users' credentials for online services, including banking services, and extort money from users by encrypting key files and then demanding payment in order to return the files to a readable state. AAEH is capable of defeating anti-virus products by blocking connections to IP addresses associated with Internet security companies and by preventing anti-virus tools from running on infected machines.  

Solution

Users are recommended to take the following actions to remediate AAEH infections:

References

Revision History

  • April 9, 2015: Initial Release

This product is provided subject to this Notification and this Privacy & Use policy.



TA15-051A: Lenovo Superfish Adware Vulnerable to HTTPS Spoofing

Original release date: February 20, 2015 | Last revised: February 24, 2015

Systems Affected

Lenovo consumer PCs that have Superfish VisualDiscovery installed.

Overview

Superfish adware installed on some Lenovo PCs install a non-unique trusted root certification authority (CA) certificate, allowing an attacker to spoof HTTPS traffic.

Description

Starting in September 2014, Lenovo pre-installed Superfish VisualDiscovery spyware on some of their PCs. This software intercepts users’ web traffic to provide targeted advertisements.  In order to intercept encrypted connections (those using HTTPS), the software installs a trusted root CA certificate for Superfish. All browser-based encrypted traffic to the Internet is intercepted, decrypted, and re-encrypted to the user’s browser by the application – a classic man-in-the-middle attack.  Because the certificates used by Superfish are signed by the CA installed by the software, the browser will not display any warnings that the traffic is being tampered with.  Since the private key can easily be recovered from the Superfish software, an attacker can generate a certificate for any website that will be trusted by a system with the Superfish software installed.  This means websites, such as banking and email, can be spoofed without a warning from the browser.

Although Lenovo has stated they have discontinued the practice of pre-installing Superfish VisualDiscovery, the systems that came with the software already installed will continue to be vulnerable until corrective actions have been taken.

To detect a system with Superfish installed, look for a HTTP GET request to:

superfish.aistcdn.com

The full request will look like:

http://superfish.aistcdn.com/set.php?ID=[GUID]&Action=[ACTION]

Where [ACTION] is at least 1, 2, or 3.  1 and then 2 are sent when a computer is turned on. 3 is sent when a computer is turned off.    

Superfish uses a vulnerable SSL decryption library by Komodia. Other applications that use the library may be similarly affected. Please refer to CERT Vulnerability Note VU#529496 for more details and updates.

Impact

A machine with Superfish VisualDiscovery installed will be vulnerable to SSL spoofing attacks without a warning from the browser.

Solution

Uninstall Superfish VisualDiscovery and associated root CA certificate

Users should uninstall Superfish VisualDiscovery. Lenovo has provided a tool to uninstall Superfish and remove all associated certificates.

It is also necessary to remove affected root CA certificates. Simply uninstalling the software does not remove the certificate. Microsoft provides guidance on deleting and managing certificates in the Windows certificate store. In the case of Superfish VisualDiscovery, the offending trusted root certification authority certificate is issued to “Superfish, Inc.”

Mozilla provides similar guidance for their software, including the Firefox and Thunderbird certificate stores.

References

Revision History

  • February 20, 2015: Initial release
  • February 20, 2015: Clarified software release dates
  • February 24, 2015: Updated description and solution details

This product is provided subject to this Notification and this Privacy & Use policy.



TA14-353A: Targeted Destructive Malware

Original release date: December 19, 2014 | Last revised: December 25, 2014

Systems Affected

Microsoft Windows

Overview

US-CERT was recently notified by a trusted third party of cyber threat actors using a Server Message Block (SMB) Worm Tool to conduct cyber exploitation activities recently targeting a major entertainment company. This SMB Worm Tool is equipped with a Listening Implant, Lightweight Backdoor, Proxy Tool, Destructive Hard Drive Tool, and Destructive Target Cleaning Tool.

SMB Worm Tool: This worm uses a brute force authentication attack to propagate via Windows SMB shares. It connects home every five minutes to send log data back to command and control (C2) infrastructure if it has successfully spread to other Windows hosts via SMB port 445. The tool also accepts new scan tasking when it connects to C2. There are two main threads: the first thread calls home and sends back logs (a list of successful SMB exploitations), and the second thread attempts to guess passwords for SMB connections. If the password is correctly guessed, a file share is established and file is copied and run on the newly-infected host.

Listening Implant: During installation of this tool, a portion of the binaries is decrypted using AES, with a key derived from the phrase "National Football League." Additionally, this implant listens for connections on TCP port 195 (for "sensvc.exe" and "msensvc.exe") and TCP port 444 (for "netcfg.dll"). Each message sent to and from this implant is preceded with its length, then XOR encoded with the byte 0x1F. Upon initial connection, the victim sends the string, "HTTP/1.1 GET /dns?\x00." The controller then responds with the string "200 www.yahoo.com!\x00" (for "sensvc.exe" and "msensvc.exe") or with the string "RESPONSE 200 OK!!" (for "netcfg.dll"). The controller sends the byte "!" (0x21) to end the network connection. This special message is not preceded with a length or XOR encoded.

Lightweight Backdoor: This is a backdoor listener that is designed as a service DLL. It includes functionality such as file transfer, system survey, process manipulation, file time matching and proxy capability. The listener can also perform arbitrary code execution and execute commands on the command line. This tool includes functionality to open ports in a victim host's firewall and take advantage of universal Plug and Play (UPNP) mechanisms to discover routers and gateway devices, and add port mappings, allowing inbound connections to victim hosts on Network Address Translated (NAT) private networks. There are no callback domains associated with this malware since connections are inbound only on a specified port number.

Proxy Tool: Implants in this malware family are typically loaded via a dropper installed as a service, then configured to listen on TCP port 443. The implant may have an associated configuration file which can contain a configurable port. This proxy tool has basic backdoor functionality, including the ability to fingerprint the victim machine, run remote commands, perform directory listings, perform process listings, and transfer files.

Destructive Hard Drive Tool: This tool is a tailored hard-drive wiping tool that is intended to destroy data past the point of recovery and to complicate the victim machine’s recovery. If the CNE operator has administrator-level privileges on the host, the program will over-write portions of up-to the first four physical drives attached, and over-write the master boot record (MBR) with a program designed to cause further damage if the hard drive is re-booted. This further results in the victim machine being non-operational with irrecoverable data (There is a caveat for machines installed with the windows 7 operating system: windows 7 machines will continue to operate in a degraded state with the targeted files destroyed until after reboot, in which the infected MBR then wipes the drive.) If the actor has user-level access, the result includes specific files being deleted and practically irrecoverable, but the victim machine would remain usable.

Destructive Target Cleaning Tool: This tool renders victim machines inoperable by overwriting the Master Boot Record. The tool is dropped and installed by another executable and consists of three parts: an executable and a dll which contain the destructive components, and an encoded command file that contains the actual destruction commands to be executed.

Network Propagation Wiper: The malware has the ability to propagate throughout the target network via built-in Windows shares. Based on the username/password provided in the configuration file and the hostname/IP address of target systems, the malware will access remote network shares in order to upload a copy of the wiper and begin the wiping process on these remote systems. The malware uses several methods to access shares on the remote systems to begin wiping files. Checking for existing shares via “\\hostname\admin$\system32” and “\\hostname\shared$\system32” or create a new share “cmd.exe /q /c net share shared$=%SystemRoot% /GRANT:everyone, FULL”. Once successful, the malware uploads a copy of the wiper file “taskhostXX.exe”, changes the file-time to match that of the built-in file “calc.exe”, and starts the remote process. The remote process is started via the command “cmd.exe /c wmic.exe /node:hostname /user:username /password:pass PROCESS CALL CREATE”. Hostname, username, and password are then obtained from the configuration file. Afterwards, the remote network share is removed via “cmd.exe /q /c net share shared$ /delete”. Once the wiper has been uploaded, the malware reports its status back to one of the four C2 IP addresses.

Technical and strategic mitigation recommendations are included in the Solution section below.

US-CERT recommends reviewing the Security Tip Handling Destructive Malware #ST13-003.

Description

Cyber threat actors are using an SMB worm to conduct cyber exploitation activities.  This tool contains five components – a listening implant, lightweight backdoor, proxy tool, destructive hard drive tool, and destructive target cleaning tool.

The SMB worm propagates throughout an infected network via brute-force authentication attacks, and connects to a C2 infrastructure.

Impact

Due to the highly destructive functionality of this malware, an organization infected could experience operational impacts including loss of intellectual property and disruption of critical systems.

Solution

Users and administrators are recommended to take the following preventive measures to protect their computer networks:

  • Use and maintain anti-virus software – Anti-virus software recognizes and protects your computer against most known viruses. It is important to keep your anti-virus software up-to-date (see Understanding Anti-Virus Software for more information).
  • Keep your operating system and application software up-to-date – Install software patches so that attackers can't take advantage of known problems or vulnerabilities. Many operating systems offer automatic updates. If this option is available, you should enable it (see Understanding Patches for more information).
  • Review Security Tip Handling Destructive Malware #ST13-003 and evaluate their capabilities encompassing planning, preparation, detection, and response for such an event.
  • Review Recommended Practices for Control Systems, and Improving Industrial Control Systems Cybersecurity with Defense-in-Depth Strategies (pdf).

The following is a list of the Indicators of Compromise (IOCs) that can be added to network security solutions to determine whether they are present on a network.

Import Hashes:

SMB worm tool:

Import hash: f6f48551d7723d87daeef2e840ae008f

Characterization: File Hash Watchlist

Notes: "SMB worm tool"

        Earliest PE compile Time: 20141001T072107Z

        Most Recent PE compile Time: 20141001T072107Z

 

Import hash: 194ae075bf53aa4c83e175d4fa1b9d89

Characterization: File Hash Watchlist

Notes: "SMB worm tool"

         Earliest PE compile Time: 20141001T120954Z

         Most Recent PE compile Time: 20141001T142138Z

 

Lightweight backdoor:

Import hash: f57e6156907dc0f6f4c9e2c5a792df48

Characterization: File Hash Watchlist

Notes: "Lightweight backdoor"

         Earliest PE compile time: 20110411T225224Z

         Latest PE compile time: 20110411T225224Z

 

Import hash: 838e57492f632da79dcd5aa47b23f8a9

Characterization: File Hash Watchlist

Notes: "Lightweight backdoor"

         Earliest PE compile time: 20110517T050015Z

         Latest PE compile time: 20110605T204508Z

 

Import hash: 11c9374cea03c3b2ca190b9a0fd2816b

Characterization: File Hash Watchlist

Notes: "Lightweight backdoor"

         Earliest PE compile time: 20110729T062417Z

         Latest PE compile time: 20110729T062958Z

 

Import hash: 7fb0441a08690d4530d2275d4d7eb351

Characterization: File Hash Watchlist

Notes: "Lightweight backdoor"

         Earliest PE compile time: 20120128T071327Z

         Latest PE compile time: 20120128T071327Z

 

Import hash: 7759c7d2c6d49c8b0591a3a7270a44da

Characterization: File Hash Watchlist

Notes: "Lightweight backdoor"

         Earliest PE compile time: 20120309T105837Z

         Latest PE compile time: 20120309T105837Z

 

Import hash: 7e48d5ba6e6314c46550ad226f2b3c67

Characterization: File Hash Watchlist

Notes: "Lightweight backdoor"

         Earliest PE compile time: 20120311T090329Z

         Latest PE compile time: 20120311T090329Z

 

Import hash: 0a87c6f29f34a09acecce7f516cc7fdb

Characterization: File Hash Watchlist

Notes: "Lightweight backdoor"

         Earliest PE compile time: 20120325T053138Z

         Latest PE compile time: 20130513T090422Z

 

Import hash: 25fb1e131f282fa25a4b0dec6007a0ce

Characterization: File Hash Watchlist

Notes: "Lightweight backdoor"

         Earliest PE compile time: 20130802T054822Z

         Latest PE compile time: 20130802T054822Z

 

Import hash: 9761dd113e7e6673b94ab4b3ad552086

Characterization: File Hash Watchlist

Notes: "Lightweight backdoor"

         Earliest PE compile time: 20130913T013016Z

         Latest PE compile time: 20130913T013016Z

 

Import hash: c905a30badb458655009799b1274205c

Characterization: File Hash Watchlist

Notes: "Lightweight backdoor"

         Earliest PE compile time: 20140205T090906Z

         Latest PE compile time: 20140205T090906Z

 

Import hash: 40adcd738c5bdc5e1cc3ab9a48b3df39

Characterization: File Hash Watchlist

Notes: "Lightweight backdoor"

         Earliest PE compile time: 20140320T152637Z

         Latest PE compile time: 20140402T023748Z

 

Import hash: 68a26b8eaf2011f16a58e4554ea576a1

Characterization: File Hash Watchlist

Notes: "Lightweight backdoor"

         Earliest PE compile time: 20140321T014949Z

         Latest PE compile time: 20140321T014949Z

 

Import hash: 74982cd1f3be3d0acfb0e6df22dbcd67

Characterization: File Hash Watchlist

Notes: "Lightweight backdoor"

         Earliest PE compile time: 20140506T020330Z

         Latest PE compile time: 20140506T020330Z

 

Proxy tool:

Import hash: 734740b16053ccc555686814a93dfbeb

Characterization: File Hash Watchlist

Notes: "Proxy tool"

         Earliest PE compile time: 20140611T064905Z

         Latest PE compile time: 20140611T064905Z

 

Import hash: 3b9da603992d8001c1322474aac25f87

Characterization: File Hash Watchlist

Notes: "Proxy tool"

         Earliest PE compile time: 20140617T035143Z

         Latest PE compile time: 20140617T035143Z

 

Import hash: e509881b34a86a4e2b24449cf386af6a

Characterization: File Hash Watchlist

Notes: "Proxy tool"

         Earliest PE compile time : 20140618T064527Z

         Latest PE compile time: 20140618T064527Z

 

Import hash: 9ab7f2bf638c9d911c2c742a574db89e

Characterization: File Hash Watchlist

Notes: "Proxy tool"

         Earliest PE compile time: 20140724T011233Z

         Latest PE compile time: 20140724T011233Z

 

Import hash: a565e8c853b8325ad98f1fac9c40fb88

Characterization: File Hash Watchlist

Notes: "Proxy tool"

         Earliest PE compile time: 20140724T065031Z

         Latest PE compile time: 20140902T135050Z

 

Import hash: 0bb82def661dd013a1866f779b455cf3

Characterization: File Hash Watchlist

Notes: "Proxy tool"

         Earliest PE compile time: 20140819T024812Z

         Latest PE compile time: 20140819T024812Z

 

Import hash: b8ffff8b57586d24e1e65cd0b0ad9173

Characterization: File Hash Watchlist

Notes: "Proxy tool"

         Earliest PE compile time: 20140902T172442Z

         Latest PE compile time: 20140902T172442Z

 

Import hash: 4ef0ad7ad4fe3ef4fb3db02cd82bface

Characterization: File Hash Watchlist

Notes: "Proxy tool"

         Earliest PE compile time: 20141024T134136Z

         Latest PE compile time: 20141024T134136Z

 

Import hash: eb435e86604abced7c4a2b11c4637a52

Characterization: File Hash Watchlist

Notes: "Proxy tool"

         Earliest PE compile time: 20140526T010925Z

         Latest PE compile time: 20140526T010925Z

 

Import hash: ed7a9c6d9fc664afe2de2dd165a9338c

Characterization: File Hash Watchlist

Notes: "Proxy tool"

         Earliest PE compile time: 20140611T064904Z

 

Destructive hard drive tool:

Import hash: 8dec36d7f5e6cbd5e06775771351c54e

Characterization: File Hash Watchlist

Notes: "Destructive hard drive tool"

         Earliest PE compile time: 20120507T151820Z

         Latest PE compile time: 20120507T151820Z

 

Import hash: a385900a36cad1c6a2022f31e8aca9f7

Characterization: File Hash Watchlist

Notes: "Destructive target cleaning tool"

         Earliest PE compile time: 20130318T003315Z

         Latest PE compile time: 20130318T003315Z

 

Import hash: 7bea4323807f7e8cf53776e24cbd71f1

Characterization: File Hash Watchlist

Notes: "Destructive target cleaning tool"

         Earliest PE compile time: 20130318T003319Z

         Latest PE compile time: 20130318T003319Z

 

Name: d1c27ee7ce18675974edf42d4eea25c6.bin

Size: 268579 bytes (268.6 KB)

MD5: D1C27EE7CE18675974EDF42D4EEA25C6

PE Compile Time: 2014-11-22 00:06:54

 

The malware has the following characteristics:

While the original filename of this file is unknown, it was likely “diskpartmg16.exe”. This file serves as a dropper. It drops destructive malware: “igfxtrayex.exe”. When the dropper file was executed, it started a second instance of itself with “-i” as an argument, and then terminated. The second instance of the dropper file installed itself as the “WinsSchMgmt” service with “-k” as a command line argument, started the service, and then terminated. The “WinsSchMgmt” service executed the file with “-k” as an argument, which started another instance of the file using “-s” as an argument. The “-s” instance dropped and executed “igfxtrayex.exe”, created “net_ver.dat”, and began generating network traffic over TCP ports 445 and 139 to victim IP addresses.

 

Name: net_ver.dat

Size: 4572 bytes (4.6 KB)  (size will vary)

MD5: 93BC819011B2B3DA8487F964F29EB934  (hash will vary)

 

This is a log file created by the dropper, and appended to as the scans progress  It contains what appear to be hostnames, IP addresses, and the number 2.   Entries in the file have the structure “HOSTNAME | IP Address | 2”.

 

Name: igfxtrayex.exe

Size: 249856 bytes (249.9 KB)

MD5: 760C35A80D758F032D02CF4DB12D3E55

PE Compile Time: 2014-11-24 04:11:08

 

This file is destructive malware: a disk wiper with network beacon capabilities. If “igfxtrayex.exe” is run with no parameters, it creates and starts a copy of itself with the “–i” argument. After 10 minutes, the “igfxtrayex.exe” makes three copies of itself and places them in the same directory from which it was executed. These copies are named according to the format “taskhostXX.exe” (where X is a randomly generated ASCII character). These copies are then executed, each with a different argument (one being “-m”, one being “-d” and the other “-w”). Network connection attempts are made to one of three hard-coded IP addresses in a random order to port 8080 or 8000. If a connection to the IP address cannot be made, it attempts to connect to another of the three IP addresses, until connections to all three IP addresses have been attempted. The following command-line string is then executed: “cmd.exe /c net stop MSExchangeIS /y”. A 120-minute (2 hour) sleep command is issued after which the computer is shut down and rebooted.

 

Name: iissvr.exe

Size: 114688 bytes (114.7 KB)

MD5: E1864A55D5CCB76AF4BF7A0AE16279BA

PE Compile Time: 2014-11-13 02:05:35

 

This file, when executed, starts a listener on localhost port 80. It has 3 files contained in the resource section; all xor’d with 0x63.

 

Name: usbdrv3_32bit.sys

Size: 24280 bytes (24.3 KB)

MD5: 6AEAC618E29980B69721158044C2E544

PE Compile Time: 2009-08-21 06:05:32

 

This SYS file is a commercially available tool that allows read/write access to files and raw disk sectors for user mode applications in Windows 2000, XP, 2003, Vista, 2008 (32-bit). It is dropped from resource ID 0x81 of “igfxtrayex.exe”.

 

Name: usbdrv3_64bit.sys

Size: 28120 bytes (28.1 KB)

MD5: 86E212B7FC20FC406C692400294073FF

PE Compile Time: 2009-08-21 06:05:35

 

This SYS file is a also a commercially available tool that allows read/write access to files and raw disk sectors for user mode applications in Windows 2000, XP, 2003, Vista, 2008 (64-bit). It is dropped from resource ID 0x83 of “igfxtrayex.exe”.

 

Name: igfxtpers.exe

Size: 91888 bytes (91.9 KB)

MD5: e904bf93403c0fb08b9683a9e858c73e

PE Compile Time: 2014-07-07 08:01:09

 

A summary of the C2 IP addresses:

IP Address

Country

Port

Filename

203.131.222.102

Thailand

8080

Diskpartmg16.exe
igfxtrayex.exe
igfxtpers.exe

217.96.33.164

Poland

8000

Diskpartmg16.exe
igfxtrayex.exe

88.53.215.64

Italy

8000

Diskpartmg16.exe
igfxtrayex.exe

200.87.126.116

Bolivia

8000

--

58.185.154.99

Singapore

8080

--

212.31.102.100

Cypress

8080

--

208.105.226.235

United States

--

igfxtpers.exe

 

Snort signatures:

SMB Worm Tool (not necessarily the tool itself):

alert tcp any any -> any any (msg:"Wiper 1"; sid:42000001; rev:1; flow:established; content:"|be 64 ba f2 a8 64|"; depth:6; offset:16; classtype:bad-unknown;)

alert tcp any any -> any any (msg:"Wiper 2"; sid:42000002; rev:1; flow:established; content:"|c9 06 d9 96 fc 37 23 5a fe f9 40 ba 4c 94 14 98|"; depth:16; classtype:bad-unknown;)

alert tcp any any -> any any (msg:"Wiper 3"; sid:42000003; rev:1; flow:established; content:"|aa 64 ba f2 56|"; depth:50; classtype:bad-unknown;)

alert ip any any -> any any (msg:"Wiper 4"; sid:42000004; rev:1; content:"|aa 74 ba f2 b9 75|"; depth:74; classtype:bad-unknown;)

alert tcp any any -> any [8000,8080] (msg:"Wiper 5"; sid:42000005; rev:1; flow:established,to_server; dsize:42; byte_test:2,=,40,0,little; content:"|04 00 00 00|"; depth:4; offset:38; classtype:bad-unknown;)

 

Listening Implant:

alert tcp any any -> any any (msg:"Listening Implant 1"; sid:42000006; rev:1; flow:established; content:"|0c 1f 1f 1f 4d 5a 4c 4f 50 51 4c 5a 3f 2d 2f 2f 3f 50 54 3e 3e 3e|"; depth:22; classtype:bad-unknown;)

alert tcp any any -> any any (msg:"Listening Implant 2"; sid:42000007; rev:1; flow:established; content:"|d3 c4 d2 d1 ce cf d2 c4 a1 b3 b1 b1 a1 ce ca a0 a0 a0|"; depth:18; classtype:bad-unknown;)

alert ip any any -> any any (msg:"Listening Implant 3"; sid:42000008; rev:1; content:"|17 08 14 13 67 0f 13 13 17 67 15 02 16 12 02 14 13 78 47 47|"; depth:24; classtype:bad-unknown;)

alert ip any any -> any any (msg:"Listening Implant 4"; sid:42000009; rev:1; content:"|4f 50 4c 4b 3f 57 4b 4b 4f 3f 4d 5a 4e 4a 5a 4c 4b 20 1f|"; depth:23; classtype:bad-unknown;)

alert ip any any -> any any (msg:"Listening Implant 5"; sid:42000010; rev:1; content:"|15 02 14 17 08 09 14 02 67 75 77 77 67 08 0c 66 66 66|"; depth:22; classtype:bad-unknown;)

alert tcp any any -> any any (msg:"Listening Implant 6"; sid:42000011; rev:1; flow:established; content:"|09 22 33 30 28 35 2c|"; fast_pattern:only; classtype:bad-unknown;)

alert tcp any any -> any any (msg:"Listening Implant 7"; sid:42000012; rev:1; flow:established; content:"|13 2f 22 35 22 67 26 35 22 29 27 33 67 28 37 22 29 67 37 28 35 33 34 69|"; fast_pattern:only; classtype:bad-unknown;)

alert tcp any any -> any any (msg:"Listening Implant 8"; sid:42000013; rev:1; flow:established; content:"|43 47 47 47 45 67 47 47 43 47 47 47 44 67 47 47|"; classtype:bad-unknown;)

alert tcp any any -> any any (msg:"Listening Implant 9"; sid:42000014; rev:1; flow:established; content:"|43 47 47 47 42 67 47 47 43 47 47 47 4f 67 47 47 43 47 47 47 43 67 47 47 43 47 47 47 4e 67 47 47|"; classtype:bad-unknown;)

alert tcp any any -> any any (msg:"Listening Implant 10"; sid:42000015; rev:1; flow:established; content:"|d1 ce d2 d5 a1 c9 d5 d5 d1 a1 d3 c4 d0 d4 c4 d2 d5 be|"; depth:18; classtype:bad-unknown;)

alert tcp any any -> any any (msg:"Listening Implant 11"; sid:42000016; rev:1; flow:established; content:"|17 08 14 13 67 0f 13 13 17 67 15 02 16 12 02 14 13 78|"; depth:18; classtype:bad-unknown;)

alert tcp any any -> any any (msg:"Listening Implant 12"; sid:42000017; rev:1; flow:established; content:"|0c 1f 1f 1f 4f 50 4c 4b 3f 57 4b 4b 4f 3f 4d 5a 4e 4a 5a 4c 4b 20|"; classtype:bad-unknown;)

 

Lightweight Backdoor:

alert tcp any 488 -> any any (msg:"Lightweight Backdoor 1"; sid:42000018; rev:1; flow:established,from_server; content:"|60 db 37 37 37 37 37 37|"; fast_pattern:only; classtype:bad-unknown;)

alert tcp any any -> any 488 (msg:"Lightweight Backdoor 2"; sid:42000019; rev:1; flow:established,to_server; content:"|60 db 37 37 37 37 37 37|"; fast_pattern:only; classtype:bad-unknown;)

alert tcp any any -> any any (msg:"Lightweight Backdoor 3"; sid:42000020; rev:1; flow:established; content:"|4c 4c|"; depth:2; offset:16; content:"|75 14 2a 2a|"; distance:4; within:4; classtype:bad-unknown;)

alert tcp any any -> any any (msg:"Lightweight Backdoor 4"; sid:42000021; rev:1; flow:established; content:"|8a 10 80 c2 67 80 f2 24 88 10|"; fast_pattern:only; content:"|8a 10 80 f2 24 80 ea 67 88 10|"; classtype:bad-unknown;)

alert tcp any 488 -> any any (msg:"Lightweight Backdoor 5"; sid:42000022; rev:1; flow:established,from_server; content:"|65 db 37 37 37 37 37 37|"; fast_pattern:only; classtype:bad-unknown;)

alert tcp any any -> any 488 (msg:"Lightweight Backdoor 6"; sid:42000023; rev:1; flow:established,to_server; content:"|65 db 37 37 37 37 37 37|"; fast_pattern:only; classtype:bad-unknown;)

alert tcp any [547,8080,133,117,189,159] -> any any (msg:"Lightweight Backdoor 7"; sid:42000024; rev:1; flow:established,from_server; content:"|7b 08 2a 2a|"; offset:17; content:"|08 2a 2a 01 00|"; distance:0; classtype:bad-unknown;)

alert tcp any any -> any any (msg:"Lightweight Backdoor 8"; sid:42000025; rev:1; flow:established; content:"|8a 10 80 ea 62 80 f2 b4 88 10|"; fast_pattern:only; content:"|8a 10 80 f2 b4 80 c2 62 88 10|"; classtype:bad-unknown;)

alert tcp any any -> any any (msg:"Lightweight Backdoor 9"; sid:42000026; rev:1; flow:established; content:"|8a 10 80 c2 4e 80 f2 79 88 10|"; fast_pattern:only; content:"|8a 10 80 f2 79 80 ea 4e 88 10|"; classtype:bad-unknown;)

alert tcp any any -> any any (msg:"Lightweight Backdoor 10"; sid:42000027; rev:1; flow:established; content:"Sleepy!@#qaz13402scvsde890"; fast_pattern:only; content:"BC435@PRO62384923412!@3!"; nocase; classtype:bad-unknown;)

 

Proxy Tool:

alert tcp any any -> any any (msg:"Proxy Tool 1"; sid:42000028; rev:1; flow:established; content:"|8a 10 80 c2 3a 80 f2 73 88 10|"; fast_pattern:only; content:"|8a 10 80 f2 73 80 ea 3a 88 10|"; classtype:bad-unknown;)

alert tcp any any -> any any (msg:"Proxy Tool 2"; sid:42000029; rev:1; flow:established; content:!"HTTP/1"; content:"|e2 1d 49 49|"; depth:4; fast_pattern; content:"|49 49 49 49|"; distance:4; within:4; classtype:bad-unknown;)

alert tcp any any -> any any (msg:"Proxy Tool 3"; sid:42000030; rev:1; flow:established; content:"|82 f4 de d4 d3 c2 ca f5 c8 c8 d3 82 fb f4 de d4 d3 c2 ca 94 95 fb d4 d1 c4 cf c8 d4 d3 89 c2 df c2 87 8a cc 87 00|"; fast_pattern:only; classtype:bad-unknown;)

 

Malware associated with the cyber threat actor:

alert tcp any any -> any [8000,8080] (msg:"WIPER4";flow: established, to_server;dsize:42;content:"|28 00|";depth:2;content:"|04 00 00 00|";offset:38;depth:4;sid:123;)

 

Host Based Indicators

Below are potential YARA signatures to detect malware binaries on host machines:

 

SMB Worm Tool:

strings:

$STR1 = "Global\\FwtSqmSession106829323_S-1-5-19"

$STR2 ="EVERYONE"

$STR3 = "y0uar3@s!llyid!07,ou74n60u7f001"

$STR4 = "\\KB25468.dat" condition:

(uintl6(0) == 0x5A4D or uint16(0) == 0xCFD0 or uint16(0) ==0xC3D4 or uint32(0) == 0x46445025 or uint32(1) == 0x6674725C) and all of them

 

Lightweight Backdoor:

strings:

$STR1 = ''NetMgStart"

$STR2 = ''Netmgmt.srg"

condition:

(uint16(0) == 0x5A4D) and all of them

 

Lightweight Backdoor:

strings:

$STR1 = "prxTroy" ascii wide nocase

condition:

(uintl6(0) == 0x5A4D or uint16(0) == 0xCFD0 or uintl6(0) == 0xC3D4 or uint32(0) == 0x46445025 or uint32(1) == 0x6674725C) and all of them

 

Lightweight Backdoor:

strings:

$strl  = { C6 45 E8 64 C6 45 E9 61 C6 45 EA 79 C6 45 EB 69 C6 45 EC 70 C6 45 ED 6D C6 45 EE 72 C6 45 EF 2E C6 45 F0 74 C6 45 F1  62 C6 45 F2 6C } // 'dayipmr.tbl' being moved to ebp

condition:

(uintl6(0) == 0x5A4D or uintl6(0) == 0xCFD0 or uint16(0) == 0xC3D4 or

uint32(0) == 0x46445025 or uint32(1) == 0x6674725C) and all of them

 

Lightweight Backdoor:

strings:

$strl  = { C6 45 F4 61 C6 45 F5 6E C6 45 F6 73 C6 45 F7 69 C6 45 F8 2E C6 45 F9 6E C6 45 FA 6C C6 45 FB 73 } // 'ansi.nls' being moved to ebp

condition:

(uint16(0) == 0x5A4D or uint16(0) == 0xCFD0 or uintl6(0) == 0xC3D4 or

uint32(0) == 0x46445025 or uint32(1) == 0x6674725C) and all of them

 

Lightweight Backdoor:

strings:

$strl  = { C6 45 F4 74 C6 45 F5 6C C6 45 F6 76 C6 45 F7 63 C6 45 F8 2E C6 45 F9 6E C6 45 FA 6C C6 45 FB 73 } // 'tlvc.nls' being moved to ebp

condition:

(uint16(0) == 0x5A4D or uint16(0) == 0xCFD0 or uint16(0) == 0xC3D4 or uint32(0) == 0x46445025 or uint32(1) == 0x6674725C) and all of them

 

Lightweight Backdoor:

strings:

$STR1 = { 8A 10 80 ?? 4E 80 ?? 79 88 10}

$STR2 = {SA 10 80?? 79 80 ?? 4E 88 10}

condition:

(uintl6(0) == 0x5A4D or uintl6(0) == 0xCFD0 or uint16(0) == 0xC3D4 or uint32(0) == 0x46445025 or uint32(1) == 0x6674725C) and all of them

 

Proxy Tool:

strings:

$STR1 = "pmsconfig.msi" wide

$STR2 = "pmslog.msi" wide

condition:

(uint16(0) == 0x5A4D or uint16(0) == 0xCFD0 or uintl6(0) == 0xC3D4 or uint32(0) == 0x46445025 or uint32(1) == 0x6674725C) and any of them

 

Proxy Tool:

strings:

$STR1 = { 82 F4 DE D4 D3 C2 CA F5 C8 C8 D3 82 FB F4 DE D4 D3 C2 CA 94 95 FB D4 Dl  C4 CF C8 D4 D3 89 C2 DF C2 87 8A CC 87 00 } // '%SystemRoot%\System32\svchost.exe -k' xor A7

condition:

(uint16(0) == 0x5A4D or uintl6(0) == 0xCFD0 or uint16(0) == 0xC3D4 or

uint32(0) == 0x46445025 or uint32(1) == 0x6674725C) and all of them

 

Proxy Tool:

strings:

$STR2 = {8A 04 17 8B FB 34 A7 46 88 02 83 C9 FF}

condition:

(uintl6(0) == 0x5A4D or uint16(0) == 0xCFD0 or uintl6(0) == 0xC3D4 or uint32(0) == 0x46445025 or uint32(1) == 0x6674725C) and $STR2

 

Destructive Hard Drive Tool:

strings:

$str0= "MZ"

$str1 = {c6 84 24 ?? ( 00 | 01 ) 00 00 }

$xorInLoop = { 83 EC 20 B9 08 00 00 00 33 D2 56 8B 74 24 30 57 8D 7C 24 08

F3 A5 8B 7C 24 30 85 FF 7E 3A 8B 74 24 2C 8A 44 24 08 53 8A 4C 24 21 8A 5C 24 2B 32 C1 8A 0C 32 32 C3 32 C8 88 0C 32 B9 1E 00 00 00 8A 5C 0C 0C 88 5C 0C 0D 49 83 F9 FF 7F F2 42 88 44 24 0C 3B D7 7C D0 5B 5F 5E 83 C4 20 C3 }

condition:

$str0 at 0 and $xorInLoop and #str1 > 300

 

Destructive Target Cleaning Tool:

strings:

$s1  = {d3000000 [4] 2c000000 [12] 95000000 [4] 6a000000 [8] 07000000}

condition:

(uintl6(0) == 0x5A4D and uintl6(uint32(0x3c)) == 0x4550) and all of them

 

Destructive Target Cleaning Tool:

strings:

$secureWipe= { 83 EC 34 53 55 8B 6C 24 40 56 57 83 CE FF 55 C7 44 24 2C D3 00 00 00 C7 44 24 30 2C 00 00 00 89 74 24 34 89 74 24 38 C7 44 24 3C 95 00 00 00 C7 44 24 40 6A 00 00 00 89 74 24 44 C7 44 24 14 07 00 00 00 FF 15 ?? ?? ?? ?? 3B C6 89 44 24 1C 0F 84 (D8 | d9) 01 00 00 33 FF 68 00 00 01 00 57 FF 15 ?? ?? ?? ?? 8B D8 3B DF 89 5C 24 14 0F 84 (BC | BD) 01 00 00 8B 44 24 1C A8 01 74 0A 24 FE 50 55 FF 15 ?? ?? ?? ?? 8B 44 24 4C 2B C7 74 20 48 74 0F 83 E8 02 75 1C C7 44 24 10 03 00 00 00 EB 12 C7 44 24 10 01 00 00 00 89 74 24 28 EB 04 89 7C 24 10 8B 44 24 10 89 7C 24 1C 3B C7 0F 8E ( 5C | 5d ) 01 00 00 8D 44 24 28 89 44 24 4C EB 03 83 CE FF 8B 4C 24 4C 8B 01 3B C6 74 17 8A D0 B9 00 40 00 00 8A F2 8B FB 8B C2 C1 E0 10 66 8B C2 F3 AB EB ( 13 | 14) 33 F6 (E8 | ff 15) ?? ?? ?? ?? 88 04 1E 46 81 FE 00 00 01 00 7C ( EF | ee) 6A 00 6A 00 6A 03 6A 00 6A 03 68 00 00 00 C0 55 FF 15 ?? ?? ?? ?? 8B F0 83 FE FF 0F 84 FA 00 00 00 8D 44 24 20 50 56 FF 15 ?? ?? ?? ?? 8B 2D ?? ?? ?? ?? 6A 02 6A 00 6A FF 56 FF D5 8D 4C 24 18 6A 00 51 6A 01 53 56 FF 15 ?? ?? ?? ?? 56 FF 15 ?? ?? ?? ?? 6A 00 6A 00 6A 00 56 FF D5 8B 44 24 24 8B 54 24 20 33 FF 33 DB 85 CO 7C 5A 7F 0A 85 D2 76 54 EB 04 8B 54 24 20 8B CA BD 00 00 01 00 2B CF 1B C3 85 C0 7F 0A 7C 04 3B CD 73 04 2B D7 8B EA 8B 44 24 14 8D 54 24 18 6A 00 52 55 50 56 FF 15 ?? ?? ?? ?? 8B 6C 24 18 8B 44 24 24 03 FD 83 D3 00 3B D8 7C BE 7F 08 8B 54 24 20 3B FA 72 B8 8B 2D ?? ?? ?? ?? 8B 5C 24 10 8B 7C 24 1C 8D 4B FF 3B F9 75 17 56 FF 15 ?? ?? ?? ?? 6A 00 6A 00 6A 00 56 FF D5 56 FF 15 ?? ?? ?? ?? 56 FF 15 ?? ?? ?? ?? 56 FF 15 ?? ?? ?? ?? 8B 4C 24 4C 8B 6C 24 48 47 83 C1 04 3B FB 8B 5C 24 14 89 7C 24 1C 89 4C 24 4C 0F 8C ( AE | AD) FE FF FF 6A 00 55 E8 ?? ?? ?? ?? 83 C4 08 53 FF 15 ?? ?? ?? ?? 5F 5E 5D 5B 83 C4 34 C3}

condition:

$secureWipe

 

Destructive Target Cleaning Tool:

strings:

$S1_CMD_Arg = ""/install'"' fullword

$S2_CMD_Parse= ""\""%s'"'  /install \""%s\""'"' fullword

$S3_CMD_Builder= ""\'"'%s\""  \""%s\'"' \""%s\'"' %s'"' fullword

condition:

all of them

 

Destructive Target Cleaning Tool:

strings:

$BATCH_SCRIPT_LN1_0 = ""goto x"" fullword

$BATCH_SCRIPT_LN1_1 = '"'del"" fullword

$BATCH_SCRIPT_LN2_0 = ""if exist"" fullword

$BATCH_SCRIPT_LN3_0 = "":x'"' fullword

$BATCH_SCRIPT_LN4_0 = ""zz%d.bat"'' fullword

condition:

(#BATCH_SCRIPT_LNl_l == 2) and all of them"

 

Destructive Target Cleaning Tool:

strings:

$MCU_DLL_ZLIB_COMPRESSED2=

{5CECABAE813CC9BCD5A542F454910428343479806F71D5521E2AOD}

condition:

$MCU_DLL_ZLIB_COMPRESSED2"

 

Destructive Target Cleaning Tool:

strings:

$MCU_INF_StartHexDec =

{010346080A30D63633000B6263750A5052322A00103D1B570A30E67F2A00130952690A50 3A0D2A000E00A26El5104556766572636C7669642E657865}

$MCU_INF_StartHexEnc =

{6C3272386958BF075230780A0A54676166024968790C7A6779588F5E47312739310163615B3D59686721CF5F2120263ElF5413531FlE004543544C55}

condition:

$MCU_INF_StartHexEnc or

$MCU_INF_StartHexDec

Destructive Target Cleaning Tool:

strings:

$ = "SetFilePointer"

$ = "SetEndOfFile"

$ = {75 17 56 ff 15 ?? ?? ?? ?? 6a 00 6a 00 6a 00 56 ffD5 56 ff 15?? ?? ??

?? 56}

condition:

(uint16(0) == 0x5A4D and uint16(uint32(0x3c)) == 0x4550) and all of them

 

Destructive Target Cleaning Tool:

strings:

$license=

{E903FFFF820050006F007200740069006F006E007300200063006F007000790072006900670068007400200052006F006200650072007400200064006500200042006100740068002C0020004A006F007200690073002000760061006E002000520061006E007400770069006A006B002C002000440065006C00690061006E000000000000000250000000000A002200CE000800EA03FFFF8200}

$PuTTY= {50007500540054005900}

condition:

(uint16(0) == 0x5A4D and uintl6(uint32(0x3c)) == 0x4550) and $license and not $PuTTY

 

Malware used by cyber threat actor:

strings:

$heapCreateFunction_0 = {33C06A003944240868001000000F94C050FF15????????85C0A3???????07436E893FEFFFF83F803A3???????0750D68F8030000E8??00000059EB0A83F8027518E8????000085C0750FFF35???????0FF15???????033C0C36A0158C3}

$heapCreateFunction =

{558BECB82C120000E8????FFFF8D8568FFFFFF5350C78568FFFFFF94000000FF1????????085C0741A83BD78FFFFFF02751183BD6CFFFFFF0572086A0158E9020100008D85D4EDFFF68901000005068???????0FF15???????085C00F84D000000033DB8D8DD4EDFFFF389DD4EDFFFF74138A013C617C083C7A7F042C20880141381975ED8D85D4EDFFFF6A165068???????0E8????000083C40C85C075088D85D4EDFFFFEB498D8564FEFFFF68040100005053FF15???????0389D64FEFFFF8D8D64FEFFFF74138A013C617C083C7A7F042C20880141381975ED8D8564FEFFFF508D85D4EDFFFF50E8????????59593BC3743E6A2C50E8????????593BC3597430408BC83818740E80393B75048819EB0141381975F26A0A5350E8????000083C40C83F802741D83F803741883F80174138D45FC50E898FEFFFF807DFC06591BC083C0035BC9C3}

$getMajorMinorLinker =

{568B7424086A00832600FF15???????06681384D5A75148B483C85C9740D03C18A481A880E8A401B8846015EC3}

$openServiceManager =

{FF15???0?0?08B?885??74????????????????5?FF15???0?0?08B?????0?0?08BF?85F?74}

condition:

all of them

 

Malware used by cyber threat actor:

strings:

$str1 = "_quit"

$str2 = "_exe"

$str3 = "_put"

$str4 = "_got"

$str5 = "_get"

$str6 ="_del"

$str7 = "_dir"

$str8 = { C7 44 24 18 1F F7}

condition:

(uintl6(0) == 0x5A4D or uintl6(0) == 0xCFD0  or uintl6(0) == 0xC3D4 or uint32(0) == 0x46445025 or uint32(1) == 0x6674725C) and all of them

 

Malware used by cyber threat actor:

strings:

$STR1 = { 50 68 80 00 00 00 68 FF FF 00 00 51 C7 44 24 1C 3a 8b 00 00 }

condition:

(uintl6(0) == 0x5A4D or uint16(0) == 0xCFD0 or uintl6(0) == 0xC3D4 or uint32(0) == 0x46445025 or uint32(1) == 0x6674725C) and all of them

 

Recommended Security Practices

Because of the highly destructive functionality of the malware, an organization infected with the malware could experience operational impacts including loss of intellectual property (IP) and disruption of critical systems. Actual impact to organizations may vary depending on the type and number of systems impacted.

Tactical Mitigations

  • Implement the indicators of compromise within your systems for detection and mitigation purposes.
  • Encourage users to transfer critical files to network shares, to allow for central backed up.
  • Execute daily backups of all critical systems.
  • Periodically execute an “offline” backup of critical files to removable media.
  • Establish emergency communications plans should network resources become unavailable.
  • Isolate any critical networks (including operations networks) from business systems.
  • Identify critical systems and evaluate the need for having on-hand spares to quickly restore service.
  • Ensure antivirus is up to date.
  • Disable credential caching for all desktop devices with particular importance on critical systems such as servers and restrict the number of cached credential for all portable devices to no more than three if possible. This can be accomplished through a Group Policy Object (GPO).
  • Disable AutoRun and Autoplay for any removable media device.
  • Prevent or limit the use of all removable media devices on systems to limit the spread or introduction of malicious software and possible exfiltration data, except where there is a valid business case for use. This business case must be approved by the organization Chief IT Security Officer, with policy/guidance on how such media should be used.
  • Consider restricting account privileges. It is our recommendation that all daily operations should be executed using standard user accounts unless administrative privileges are required for that specific function. Configure all standard user accounts to prevent the execution and installation of any unknown or unauthorized software. Both standard and administrative accounts should have access only to services required for nominal daily duties, enforcing the concept of separation of duties. Lastly, disable Web and email capabilities on administrative accounts. Compromise of admin accounts is one vector that allows malicious activity to become truly persistent in a network environment.
  • Ensure that password policy rules are enforced and Admin password values are changed periodically.
  • Consider prohibiting hosts within the production environment or DMZ from sharing an Active Directory enterprise with hosts on other networks. Each environment should have separate forests within Active Directory, with no trust relationships allowed between the forests if at all possible. If necessary, the trust relationships should be one-way with the low integrity environment trusting the higher integrity environment.
  • Consider deployment of a coaching page with click through acceptance; these are traditionally deployed in an environment to log the acceptance of network acceptable use policy or to notify users of monitoring. Coaching pages also provide some measure of protection from automated malicious activity. This occurs because automated malware is normally incapable of physically clicking an acceptance radial button. Automated malware is traditionally hardcoded to execute, then retrieve commands or additional executables from the Internet. If the malware is unable to initiate an active connection, the full train of infection is potentially halted. The danger still exists that the physical user will authorize access, but through the use of coaching pages, infections can be limited or at least the rate of infection reduced.
  • Monitor logs -- Maintain and actively monitor a centralized logging solution that keeps track of all anomalous and potentially malicious activity.
  • Ensure that all network operating systems, web browsers, and other related network hardware and software remain updated with all current patches and fixes.

Strategic Mitigations

  • Organizations should review Security Tip Handling Destructive Malware #ST13-003 and evaluate their capabilities encompassing planning, preparation, detection, and response for such an event.
  • Always keep your patch levels up to date, especially on computers that host public services accessible through the firewall, such as HTTP, FTP, mail, and DNS services.
  • Build host systems, especially critical systems such as servers, with only essential applications and components required to perform the intended function. Any unused applications or functions should be removed or disabled, if possible, to limit the attack surface of the host.
  • Implement network segmentation through V-LANs to limit the spread of malware.
  • Consider the deployment of Software Restriction Policy set to only allow the execution of approved software (application whitelisting)
  • Recommend the whitelisting of legitimate executable directories to prevent the execution of potentially malicious binaries.
  • Consider the use of two-factor authentication methods for accessing privileged root level accounts or systems.
  • Consider deploying a two-factor authentication through a hardened IPsec/VPN gateway with split-tunneling prohibited for secure remote access.
  • Deny direct Internet access, except through the use of proxies for Enterprise servers and workstations. Perform regular content filtering at the proxies or external firewall points of presence. Also consider the deployment of an explicit versus transparent proxy policy.
  • Implement a Secure Socket Layer (SSL) inspection capability to inspect both ingress and egress encrypted network traffic for potential malicious activity.
  • Isolate network services, such as email and Web application servers by utilizing a secure multi-tenant virtualization technology. This will limit the damage sustained from a compromise or attack of a single network component.
  • Implement best practice guidance and policy to restrict the use of non-Foundation assets for processing or accessing Foundation-controlled data or systems (e.g., working from home, or using a personal device while at the office). It is difficult to enforce corporate policies, detect intrusions, and conduct forensic analysis or remediate compromises on non-corporate owned devices.
  • Minimize network exposure for all control system devices. Control system devices should not directly face the Internet.
  • Place control system networks behind firewalls, and isolate or air gap them from the business network.
  • When remote access is required, use secure methods, such as Virtual Private Networks (VPNs), recognizing that VPN is only as secure as the connected devices.
  • Industrial Control System (ICS)-CERT and US-CERT remind organizations to perform proper impact analysis and risk assessment prior to taking defensive measures.

References

Revision History

  • December 19, 2014: Initial Release
  • December 24, 2014: Updates to information in the Solutions section.

This product is provided subject to this Notification and this Privacy & Use policy.



TA14-329A: Regin Malware

Original release date: November 25, 2014

Systems Affected

Microsoft Windows NT, 2000, XP, Vista, and 7

Overview

On November 24, 2014, Symantec released a report on Regin, a sophisticated backdoor Trojan used to conduct intelligence-gathering campaigns. At this time, the Regin campaign has not been identified targeting any organizations within the United States.

Description

Regin is a multi-staged, modular threat—meaning it has a number of components, each dependent on others to perform an attack. Each of the five stages is hidden and encrypted, with the exception of the first stage. The modular design poses difficulties to analysis, as all components must be available in order to fully understand the Trojan.  

Impact

Regin is a remote access Trojan (RAT), able to take control of input devices, capture credentials, monitor network traffic, and gather information on processes and memory utilization. The complex design provides flexibility to actors, as they can load custom features tailored to individual targets. [1]

Solution

Users and administrators are recommended to take the following preventive measures to protect their computer networks:

  • Use and maintain anti-virus software – Anti-virus software recognizes and protects your computer against most known viruses. It is important to keep your anti-virus software up-to-date (see Understanding Anti-Virus Software for more information). [2]
  • Keep your operating system and application software up-to-date – Install software patches so that attackers can't take advantage of known problems or vulnerabilities. Many operating systems offer automatic updates. If this option is available, you should enable it (see Understanding Patches for more information).

The following is a list of the Indicators of Compromise (IOCs) that can be added to network security solutions to determine whether they are present on a network.

MD5s: [1]

Stage 1 files, 32 bit:

06665b96e293b23acc80451abb413e50

187044596bc1328efa0ed636d8aa4a5c

1c024e599ac055312a4ab75b3950040a

2c8b9d2885543d7ade3cae98225e263b

4b6b86c7fec1c574706cecedf44abded

6662c390b2bbbd291ec7987388fc75d7

b269894f434657db2b15949641a67532

b29ca4f22ae7b7b25f79c1d4a421139d

b505d65721bb2453d5039a389113b566

26297dc3cd0b688de3b846983c5385e5

ba7bb65634ce1e30c1e5415be3d1db1d

bfbe8c3ee78750c3a520480700e440f8

d240f06e98c8d3e647cbf4d442d79475

ffb0b9b5b610191051a7bdf0806e1e47

Unusual stage 1 files apparently compiled from various public source codes merged with malicious code:

01c2f321b6bfdb9473c079b0797567ba

47d0e8f9d7a6429920329207a32ecc2e

744c07e886497f7b68f6f7fe57b7ab54

db405ad775ac887a337b02ea8b07fddc

Stage 1, 64-bit system infection:

bddf5afbea2d0eed77f2ad4e9a4f044d

c053a0a3f1edcbbfc9b51bc640e808ce

e63422e458afdfe111bd0b87c1e9772c

Stage 2, 32 bit:

18d4898d82fcb290dfed2a9f70d66833

b9e4f9d32ce59e7c4daf6b237c330e25

Stage 2, 64 bit:

d446b1ed24dad48311f287f3c65aeb80

Stage 3, 32 bit:

8486ec3112e322f9f468bdea3005d7b5

da03648948475b2d0e3e2345d7a9bbbb

Stage 4, 32 bit:

1e4076caa08e41a5befc52efd74819ea

68297fde98e9c0c29cecc0ebf38bde95

6cf5dc32e1f6959e7354e85101ec219a

885dcd517faf9fac655b8da66315462d

a1d727340158ec0af81a845abd3963c1

Stage 4, 64 bit:

de3547375fbf5f4cb4b14d53f413c503

Note: Stages 2, 3, and 4 do not appear on infected systems as real files on disk. Hashes are provided for research purposes only.

Registry branches used to store malware stages 2 and 3:

\REGISTRY\Machine\System\CurrentControlSet\Control\RestoreList

\REGISTRY\Machine\System\CurrentControlSet\Control\Class\{39399744-44FC-AD65-474B-E4DDF-8C7FB97}

\REGISTRY\Machine\System\CurrentControlSet\Control\Class\{3F90B1B4-58E2-251E-6FFE-4D38C5631A04}

\REGISTRY\Machine\System\CurrentControlSet\Control\Class\{4F20E605-9452-4787-B793-D0204917CA58}

\REGISTRY\Machine\System\CurrentControlSet\Control\Class\{9B9A8ADB-8864-4BC4-8AD5-B17DFDBB9F58}

IP IOCs [3]:

61.67.114.73

202.71.144.113

203.199.89.80

194.183.237.145

References

Revision History

  • November 25, 2014: Initial Release

This product is provided subject to this Notification and this Privacy & Use policy.



TA14-323A: Microsoft Windows Kerberos KDC Remote Privilege Escalation Vulnerability

Original release date: November 19, 2014 | Last revised: November 25, 2014

Systems Affected

  • Microsoft Windows Vista, 7, 8, and 8.1
  • Microsoft Server 2003, Server 2008, Server 2008 R2, Server 2012, and Server 2012 R2

Overview

A remote escalation of privilege vulnerability exists in implementations of Kerberos Key Distribution Center (KDC) in Microsoft Windows which could allow a remote attacker to take control of a vulnerable system. [1]

Description

The Microsoft Windows Kerberos KDC fails to properly check service tickets for valid signatures, which can allow aspects of the service ticket to be forged. The improper check allows an attacker to escalate valid domain user account privileges to those of a domain administrator account, which renders the entire domain vulnerable to compromise.

At the time this release was issued, Microsoft was aware of limited, targeted attacks attempting to exploit this vulnerability.

Impact

A valid domain user can pass invalid domain administrator credentials, gain access and compromise any system on the domain, including the domain controller. [2]

Solution

An update is available from Microsoft. Please see Microsoft Security Bulletin MS14-068 and Microsoft Research Security and Defense Blog for more details, and apply the necessary updates.[1, 3

References

Revision History

  • November 19, 2014: Initial Draft
  • November 25, 2014: Revised formatting

This product is provided subject to this Notification and this Privacy & Use policy.



TA14-318B: Microsoft Windows OLE Automation Array Remote Code Execution Vulnerability

Original release date: November 14, 2014

Systems Affected

  • Microsoft Windows Vista, 7, 8, 8.1, RT, and RT 8.1
  • Microsoft Server 2003, Server 2008, Server 2008 R2, Server 2012, and Server 2012 R2

Overview

A vulnerability in Microsoft Windows Object Linking and Embedding (OLE) could allow remote code execution if a user views a specially-crafted web page in Internet Explorer.[1]

Description

The Microsoft Windows OLE OleAut32.dll library provides the SafeArrayRedim function that allows resizing of SAFEARRAY objects in memory.[2] In certain circumstances, this library does not properly check sizes of arrays when an error occurs. The improper size allows an attacker to manipulate memory in a way that can bypass the Internet Explorer Enhanced Protected Mode (EPM) sandbox as well as the Enhanced Mitigation Experience Toolkit (EMET).

This vulnerability can be exploited using a specially-crafted web page utilizing VBscript in Internet Explorer. However, it may impact other software that makes use of OleAut32.dll and VBscript.

Exploit code is publicly available for this vulnerability. Additional details may be found in CERT/CC Vulnerability Note VU#158647.

Impact

Arbitrary code can be run on the computer with user privileges. If the user is an administrator, the attacker may run arbitrary code as an administrator, fully compromising the system. 

Solution

An update is available from Microsoft.[3] Please see Microsoft Security Bulletin MS14-064 for more details and mitigation guidance, and apply the necessary updates.

References

Revision History

  • November 14, 2014: Initial Release

This product is provided subject to this Notification and this Privacy & Use policy.


Courtesy US-CERT

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