metaMain is a backdoor used by Metador to maintain long-term access to compromised machines; it has also been used to decrypt Mafalda into memory.[1][2]

ID: S1059
Platforms: Windows
Contributors: Massimiliano Romano, BT Security
Version: 1.1
Created: 24 January 2023
Last Modified: 11 April 2024

Techniques Used

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

metaMain can use HTTP for C2 communications.[1][2]

Enterprise T1560 .003 Archive Collected Data: Archive via Custom Method

metaMain has used XOR-based encryption for collected files before exfiltration.[1]

Enterprise T1005 Data from Local System

metaMain can collect files and system information from a compromised host.[1][2]

Enterprise T1074 .001 Data Staged: Local Data Staging

metaMain has stored the collected system files in a working directory.[1][2]

Enterprise T1140 Deobfuscate/Decode Files or Information

metaMain can decrypt and load other modules.[1]

Enterprise T1573 .001 Encrypted Channel: Symmetric Cryptography

metaMain can encrypt the data that it sends and receives from the C2 server using an RC4 encryption algorithm.[1][2]

Enterprise T1546 .003 Event Triggered Execution: Windows Management Instrumentation Event Subscription

metaMain registered a WMI event subscription consumer called "hard_disk_stat" to establish persistence.[1]

Enterprise T1041 Exfiltration Over C2 Channel

metaMain can upload collected files and data to its C2 server.[2]

Enterprise T1083 File and Directory Discovery

metaMain can recursively enumerate files in an operator-provided directory.[1][2]

Enterprise T1574 .002 Hijack Execution Flow: DLL Side-Loading

metaMain can support an HKCMD sideloading start method.[2]

Enterprise T1070 .004 Indicator Removal: File Deletion

metaMain has deleted collected items after uploading the content to its C2 server.[1][2]

.006 Indicator Removal: Timestomp

metaMain can change the CreationTime, LastAccessTime, and LastWriteTime file time attributes when executed with SYSTEM privileges.[2]

Enterprise T1105 Ingress Tool Transfer

metaMain can download files onto compromised systems.[1][2]

Enterprise T1056 Input Capture

metaMain can log mouse events.[2]

.001 Keylogging

metaMain has the ability to log keyboard events.[1][2]

Enterprise T1112 Modify Registry

metaMain can write the process ID of a target process into the HKEY_LOCAL_MACHINE\SOFTWARE\DDE\tpid Registry value as part of its reflective loading activity.[2]

Enterprise T1106 Native API

metaMain can execute an operator-provided Windows command by leveraging functions such as WinExec, WriteFile, and ReadFile.[1][2]

Enterprise T1095 Non-Application Layer Protocol

metaMain can establish an indirect and raw TCP socket-based connection to the C2 server.[1][2]

Enterprise T1027 .013 Obfuscated Files or Information: Encrypted/Encoded File

metaMain's module file has been encrypted via XOR.[2]

Enterprise T1057 Process Discovery

metaMain can enumerate the processes that run on the platform.[1][2]

Enterprise T1055 Process Injection

metaMain can inject the loader file, Speech02.db, into a process.[1]

Enterprise T1090 .001 Proxy: Internal Proxy

metaMain can create a named pipe to listen for and send data to a named pipe-based C2 server.[2]

Enterprise T1620 Reflective Code Loading

metaMain has reflectively loaded a DLL to read, decrypt, and load an orchestrator file.[1]

Enterprise T1113 Screen Capture

metaMain can take and save screenshots.[1][2]

Enterprise T1082 System Information Discovery

metaMain can collect the computer name from a compromised host.[2]

Enterprise T1033 System Owner/User Discovery

metaMain can collect the username from a compromised host.[2]

Enterprise T1205 .001 Traffic Signaling: Port Knocking

metaMain has authenticated itself to a different implant, Cryshell, through a port knocking and handshake procedure.[1]

Enterprise T1497 .003 Virtualization/Sandbox Evasion: Time Based Evasion

metaMain has delayed execution for five to six minutes during its persistence establishment process.[2]

Groups That Use This Software

ID Name References
G1013 Metador