Suspicious Modification of etc passwd Following Linux Kernel Exploit

ATT&CK techniques

Priv Esc

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
- T1068Exploitation for Privilege Escalation
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects writes to etc passwd by a non package management process as seen in post exploitation of the Copy Fail and DirtyFrag Linux page cache bugs in Elastic research. Corrupting or appending to passwd is used to inject a privileged account after a kernel primitive grants arbitrary write, indicating successful escalation.

Reporting behind it

Related detections9 linkedT1068 — drag to rearrange

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Suspicious EDRKillShifter Vulnerable Driver Load from User Temp Directory (via image_load)

Suspicious Process Explorer Kernel Driver Dropped as PED.sys via File Creation (via file_event)

Malicious Payload Download From copy.fail Exploit Host on Linux (via process_creation)

Suspicious su Execution From Uncommon Parent Process on Linux (via process_creation)

Possible noPac sAMAccountName Spoofing via Machine Account Rename

Suspicious Modification of etc passwd Following Linux Kernel Exploit

Pivot detection · T1068 · 9 related

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