C0021

C0021 was a spearphishing campaign conducted in November 2018 that targeted public sector institutions, non-governmental organizations (NGOs), educational institutions, and private-sector corporations in the oil and gas, chemical, and hospitality industries. The majority of targets were located in the US, particularly in and around Washington D.C., with other targets located in Europe, Hong Kong, India, and Canada. C0021's technical artifacts, tactics, techniques, and procedures (TTPs), and targeting overlap with previous suspected APT29 activity.[1][2]

ID: C0021
First Seen:  November 2018 [2][1]
Last Seen:  November 2018 [2][1]
Version: 1.0
Created: 15 March 2023
Last Modified: 05 April 2023

Techniques Used

Domain ID Name Use
Enterprise T1583 .001 Acquire Infrastructure: Domains

For C0021, the threat actors registered domains for use in C2.[2]

Enterprise T1071 .001 Application Layer Protocol: Web Protocols

During C0021, the threat actors used HTTP for some of their C2 communications.[2]

Enterprise T1059 .001 Command and Scripting Interpreter: PowerShell

During C0021, the threat actors used obfuscated PowerShell to extract an encoded payload from within an .LNK file.[2][1]

Enterprise T1584 .001 Compromise Infrastructure: Domains

For C0021, the threat actors used legitimate but compromised domains to host malicious payloads.[1]

Enterprise T1140 Deobfuscate/Decode Files or Information

During C0021, the threat actors deobfuscated encoded PowerShell commands including use of the specific string 'FromBase'+0x40+'String', in place of FromBase64String which is normally used to decode base64.[2][1]

Enterprise T1573 .002 Encrypted Channel: Asymmetric Cryptography

During C0021, the threat actors used SSL via TCP port 443 for C2 communications.[2]

Enterprise T1105 Ingress Tool Transfer

During C0021, the threat actors downloaded additional tools and files onto victim machines.[1][2]

Enterprise T1095 Non-Application Layer Protocol

During C0021, the threat actors used TCP for some C2 communications.[2]

Enterprise T1027 .009 Obfuscated Files or Information: Embedded Payloads

For C0021, the threat actors embedded a base64-encoded payload within a LNK file.[1]

.010 Obfuscated Files or Information: Command Obfuscation

During C0021, the threat actors used encoded PowerShell commands.[2][1]

Enterprise T1588 .002 Obtain Capabilities: Tool

For C0021, the threat actors used Cobalt Strike configured with a modified variation of the publicly available Pandora Malleable C2 Profile.[2][1]

Enterprise T1566 .002 Phishing: Spearphishing Link

During C0021, the threat actors sent phishing emails with unique malicious links, likely for tracking victim clicks.[2][1]

Enterprise T1608 .001 Stage Capabilities: Upload Malware

For C0021, the threat actors uploaded malware to websites under their control.[2][1]

Enterprise T1218 .011 System Binary Proxy Execution: Rundll32

During C0021, the threat actors used rundll32.exe to execute the Cobalt Strike Beacon loader DLL.[2]

Enterprise T1204 .001 User Execution: Malicious Link

During C0021, the threat actors lured users into clicking a malicious link which led to the download of a ZIP archive containing a malicious .LNK file.[2]

Software

ID Name Description
S0154 Cobalt Strike

[2][1]

References