Potential PetitPotam Attack Via EFS RPC Calls
Detects usage of the windows RPC library Encrypting File System Remote Protocol (MS-EFSRPC). Variations of this RPC are used within the attack refereed to as PetitPotam. The usage of this RPC function should be rare…
Description
Detects usage of the windows RPC library Encrypting File System Remote Protocol (MS-EFSRPC). Variations of this RPC are used within the attack refereed to as PetitPotam. The usage of this RPC function should be rare if ever used at all. Thus usage of this function is uncommon enough that any usage of this RPC function should warrant further investigation to determine if it is legitimate. View surrounding logs (within a few minutes before and after) from the Source IP to. Logs from from the Source IP would include dce_rpc, smb_mapping, smb_files, rdp, ntlm, kerberos, etc..'
Detection logic
Detection requirements
Known benign triggers
- Uncommon but legitimate windows administrator or software tasks that make use of the Encrypting File System RPC Calls. Verify if this is common activity (see description).
MITRE ATT&CK mappings
0 exclusive techniques.This is coverage no other published rule has; it is not this rule's total technique count.
References
| Reference | Cited by |
|---|---|
| github.com/topotam/PetitPotam/blob/d83ac8f2dd34654628c17490f99106eb128e7d1e/PetitPotam/PetitPotam.cpp | Only this detection cites it |
| msrc.microsoft.com/update-guide/vulnerability/ADV210003 | Only this detection cites it |
| threatpost.com/microsoft-petitpotam-poc/168163/ | Only this detection cites it |
| vx-underground.org/archive/Symantec/windows-vista-network-attack-07-en.pdf | Only this detection cites it |
From the source
- At source
- Open at source
- Upstream identifier
- 4096842a-8f9f-4d36-92b4-d0b2a62f9b2a
- Tagged by the source as
- attack.collectionattack.credential-access
Licence
- Published under
- Detection Rule License 1.1Read the licence
- Attribution
- Required
Authorship
- Written by
- Published
- Aug 26, 2026
- Version
- 1