Xbash

Xbash is a malware family that has targeted Linux and Microsoft Windows servers. The malware has been tied to the Iron Group, a threat actor group known for previous ransomware attacks. Xbash was developed in Python and then converted into a self-contained Linux ELF executable by using PyInstaller.[1]

ID: S0341
Type: MALWARE
Platforms: Windows, Linux
Version: 1.2
Created: 30 January 2019
Last Modified: 23 June 2020

Techniques Used

Domain ID Name Use
Enterprise T1071 .001 Application Layer Protocol: Web Protocols

Xbash uses HTTP for C2 communications.[1]

Enterprise T1547 .001 Boot or Logon Autostart Execution: Registry Run Keys / Startup Folder

Xbash can create a Startup item for persistence if it determines it is on a Windows system.[1]

Enterprise T1110 .001 Brute Force: Password Guessing

Xbash can obtain a list of weak passwords from the C2 server to use for brute forcing as well as attempt to brute force services with open ports.[1][2]

Enterprise T1059 .005 Command and Scripting Interpreter: Visual Basic

Xbash can execute malicious VBScript payloads on the victim’s machine.[1]

.001 Command and Scripting Interpreter: PowerShell

Xbash can use scripts to invoke PowerShell to download a malicious PE executable or PE DLL for execution.[1]

.007 Command and Scripting Interpreter: JavaScript/JScript

Xbash can execute malicious JavaScript payloads on the victim’s machine.[1]

Enterprise T1485 Data Destruction

Xbash has destroyed Linux-based databases as part of its ransomware capabilities.[1]

Enterprise T1486 Data Encrypted for Impact

Xbash has maliciously encrypted victim's database systems and demanded a cryptocurrency ransom be paid.[1]

Enterprise T1203 Exploitation for Client Execution

Xbash can attempt to exploit known vulnerabilities in Hadoop, Redis, or ActiveMQ when it finds those services running in order to conduct further execution.[1][2]

Enterprise T1105 Ingress Tool Transfer

Xbash can download additional malicious files from its C2 server.[1]

Enterprise T1046 Network Service Scanning

Xbash can perform port scanning of TCP and UDP ports.[1]

Enterprise T1053 .003 Scheduled Task/Job: Cron

Xbash can create a cronjob for persistence if it determines it is on a Linux system.[1]

Enterprise T1218 .005 Signed Binary Proxy Execution: Mshta

Xbash can use mshta for executing scripts.[1]

.010 Signed Binary Proxy Execution: Regsvr32

Xbash can use regsvr32 for executing scripts.[1]

Enterprise T1016 System Network Configuration Discovery

Xbash can collect IP addresses and local intranet information from a victim’s machine.[1]

Enterprise T1102 .001 Web Service: Dead Drop Resolver

Xbash can obtain a webpage hosted on Pastebin to update its C2 domain list.[1]

References