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FELIXROOT is a backdoor that has been used to target Ukrainian victims. [1]

ID: S0267
Associated Software: GreyEnergy mini
Platforms: Windows
Version: 2.0
Created: 17 October 2018
Last Modified: 30 January 2019

Associated Software Descriptions

Name Description
GreyEnergy mini [2]

Techniques Used

Domain ID Name Use
Enterprise T1059 Command-Line Interface

FELIXROOT opens a remote shell to execute commands on the infected system.[1][2]

Enterprise T1043 Commonly Used Port

FELIXROOT uses Port Numbers 443, 8443, and 8080 for C2 communications.[1][2]

Enterprise T1022 Data Encrypted

FELIXROOT encrypts collected data with AES and Base64 and then sends it to the C2 server.[1]

Enterprise T1107 File Deletion

FELIXROOT deletes the .LNK file from the startup directory as well as the dropper components.[1]

Enterprise T1112 Modify Registry

FELIXROOT deletes the Registry key HKCU\Software\Classes\Applications\rundll32.exe\shell\open.[1]

Enterprise T1027 Obfuscated Files or Information

FELIXROOT encrypts strings in the backdoor using a custom XOR algorithm.[1][2]

Enterprise T1057 Process Discovery

FELIXROOT collects a list of running processes.[2]

Enterprise T1012 Query Registry

FELIXROOT queries the Registry for specific keys for potential privilege escalation and proxy information. FELIXROOT has also used WMI to query the Windows Registry.[1][2]

Enterprise T1060 Registry Run Keys / Startup Folder

FELIXROOT adds a shortcut file to the startup folder for persistence.[2]

Enterprise T1105 Remote File Copy

FELIXROOT downloads and uploads files to and from the victim’s machine.[1][2]

Enterprise T1085 Rundll32

FELIXROOT uses Rundll32 for executing the dropper program.[1][2]

Enterprise T1064 Scripting

FELIXROOT executes batch scripts on the victim’s machine.[1]

Enterprise T1063 Security Software Discovery

FELIXROOT checks for installed security software like antivirus and firewall.[2]

Enterprise T1023 Shortcut Modification

FELIXROOT creates a .LNK file for persistence.[2]

Enterprise T1071 Standard Application Layer Protocol

FELIXROOT uses HTTP and HTTPS to communicate with the C2 server.[1][2]

Enterprise T1082 System Information Discovery

FELIXROOT collects the victim’s computer name, processor architecture, OS version, volume serial number, and system type.[1][2]

Enterprise T1016 System Network Configuration Discovery

FELIXROOT collects information about the network including the IP address and DHCP server.[2]

Enterprise T1033 System Owner/User Discovery

FELIXROOT collects the username from the victim’s machine.[1][2]

Enterprise T1124 System Time Discovery

FELIXROOT gathers the time zone information from the victim’s machine.[2]

Enterprise T1047 Windows Management Instrumentation

FELIXROOT uses WMI to query the Windows Registry.[2]