CHOPSTICK

CHOPSTICK is a malware family of modular backdoors used by APT28. It has been used since at least 2012 and is usually dropped on victims as second-stage malware, though it has been used as first-stage malware in several cases. It has both Windows and Linux variants. [1] [2] [3] [4] It is tracked separately from the X-Agent for Android.

ID: S0023
Associated Software: Backdoor.SofacyX, SPLM, Xagent, X-Agent, webhp
Type: MALWARE
Platforms: Windows, Linux
Contributors: Richard Gold, Digital Shadows
Version: 2.3
Created: 31 May 2017
Last Modified: 26 March 2023

Associated Software Descriptions

Name Description
Backdoor.SofacyX

[5]

SPLM

[2] [3]

Xagent

[2] [3]

X-Agent

[2] [3]

webhp

[3]

Techniques Used

Domain ID Name Use
Enterprise T1090 .001 代理: Internal Proxy

CHOPSTICK used a proxy server between victims and the C2 server.[2]

Enterprise T1112 修改注册表

CHOPSTICK may modify Registry keys to store RC4 encrypted configuration information.[1]

Enterprise T1573 .001 加密通道: Symmetric Cryptography

CHOPSTICK encrypts C2 communications with RC4.[2]

.002 加密通道: Asymmetric Cryptography

CHOPSTICK encrypts C2 communications with TLS.[2]

Enterprise T1568 .002 动态解析: Domain Generation Algorithms

CHOPSTICK can use a DGA for Fallback Channels, domains are generated by concatenating words from lists.[6]

Enterprise T1059 命令与脚本解释器

CHOPSTICK is capable of performing remote command execution.[7][2]

Enterprise T1008 回退信道

CHOPSTICK can switch to a new C2 channel if the current one is broken.[2]

Enterprise T1113 屏幕捕获

CHOPSTICK has the capability to capture screenshots.[4]

Enterprise T1071 .001 应用层协议: Web Protocols

Various implementations of CHOPSTICK communicate with C2 over HTTP.[2]

.003 应用层协议: Mail Protocols

Various implementations of CHOPSTICK communicate with C2 over SMTP and POP3.[2]

Enterprise T1083 文件和目录发现

An older version of CHOPSTICK has a module that monitors all mounted volumes for files with the extensions .doc, .docx, .pgp, .gpg, .m2f, or .m2o.[2]

Enterprise T1012 查询注册表

CHOPSTICK provides access to the Windows Registry, which can be used to gather information.[1]

Enterprise T1027 .011 混淆文件或信息: Fileless Storage

CHOPSTICK may store RC4 encrypted configuration information in the Windows Registry.[1]

Enterprise T1497 虚拟化/沙盒规避

CHOPSTICK includes runtime checks to identify an analysis environment and prevent execution on it.[1]

Enterprise T1518 .001 软件发现: Security Software Discovery

CHOPSTICK checks for antivirus and forensics software.[1]

Enterprise T1105 输入工具传输

CHOPSTICK is capable of performing remote file transmission.[7]

Enterprise T1056 .001 输入捕获: Keylogging

CHOPSTICK is capable of performing keylogging.[7][2][4]

Enterprise T1091 通过可移动媒体复制

Part of APT28's operation involved using CHOPSTICK modules to copy itself to air-gapped machines and using files written to USB sticks to transfer data and command traffic.[1][8][9]

Enterprise T1092 通过可移动媒体通信

Part of APT28's operation involved using CHOPSTICK modules to copy itself to air-gapped machines, using files written to USB sticks to transfer data and command traffic.[1][2][8]

Groups That Use This Software

ID Name References
G0007 APT28

[1][10][11][9]

References