RoKRAT Shellcode and Steganographic Threats: Analysis and EDR Response Strategies
2025-08-03 • Genians •
https://www.genians.co.kr/en/blog/threat_intelligence/rokrat_shellcode_steganographic
Genians identifies a new RoKRAT variant used by APT37 and delivered in South Korea through a compressed archive containing an unusually large malicious LNK file. The shortcut masquerades as a national intelligence and counterintelligence manuscript and embeds a decoy HWP document, shellcode, PowerShell commands, and a batch script. The execution flow runs batch and PowerShell stages that decode shellcode with XOR operations, produce a 32-bit executable, and inject payloads into hardcoded Windows processes such as mspaint.exe, with a later variant switching to notepad.exe. The embedded PDB path containing InjectShellcode, and later a Weapon directory, gives defenders useful variant-tracking evidence while showing continued fileless and shortcut-based tradecraft tied to APT37.
Indicators of Compromise
| Type | Value | First Seen | Last Seen |
|---|---|---|---|
| [email protected] | 2025-08-03 | 2026-04-12 | |
| HASH | ccb6ca4cb385db50dad2e3b7c68a90d… | 2025-08-03 | 2026-01-14 |
| HASH | 90bf1f20f962d04f8ae3f936d0f9046… | 2025-06-09 | 2025-08-29 |
| DOMAIN | cloud-api.yandex.net | 2018-02-27 | 2025-08-29 |
| HASH | 41d9b6d8cf0fff85bf35327d4b94db6… | 2025-08-03 | 2025-08-03 |
| HASH | 9eca7ab62e3ad40b79116ad713462e3… | 2025-08-03 | 2025-08-03 |
| HASH | ca56720610400d6da773ffa4cce5b24… | 2025-08-03 | 2025-08-03 |
| HASH | 7d514021c472e6e17f587ed30555d3f… | 2025-08-03 | 2025-08-03 |
| HASH | bf7d5020dcd7777509b7b542255814c… | 2025-08-03 | 2025-08-03 |
| HASH | 7ee4326c5d0e6a30c1a9bdec045d670… | 2025-08-03 | 2025-08-03 |
| HASH | e27467f7fdfa721e917384542ce10cc… | 2025-08-03 | 2025-08-03 |
| HASH | 6a2d984ef3fa0de9b9feb5f55838120… | 2025-08-03 | 2025-08-03 |
| HASH | 3fa06c290c477c133ca58512c7852fc… | 2025-08-03 | 2025-08-03 |
| [email protected] | 2025-08-03 | 2025-08-03 | |
| [email protected] | 2025-08-03 | 2025-08-03 | |
| [email protected] | 2025-08-03 | 2025-08-03 |