Malicious COM Hijack of PSFactoryBuffer InprocServer32

ATT&CK techniques

Persistence → Priv Esc

Recon
Resource Dev
Initial Access
Execution
Persistence
- T1546.015Component Object Model Hijacking
Priv Esc
- T1546.015Component Object Model Hijacking
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects modification of the InprocServer32 value under the CLSID {1299CF18-C4F5-4B6A-BB0F-2299F0398E27} PSFactoryBuffer key in the per-user registry hive, a COM hijack used by RomCom for persistence and execution after WinRAR exploitation. Redirecting this COM server class to an attacker DLL causes malicious code to load when the COM object is instantiated.

Reporting behind it

Related detections9 linkedT1546.015 — drag to rearrange

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Malicious COM Hijack of PSFactoryBuffer InprocServer32

Pivot detection · T1546.015 · 9 related

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