Suspicious su to Root with Blank Invoking User for CopyFail LPE (via auth)

ATT&CK techniques

Priv Esc → Defense Evasion

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
- T1068Exploitation for Privilege Escalation
- T1548.003Sudo and Sudo Caching
Defense Evasion
- T1548.003Sudo and Sudo Caching
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects malformed su authentication records where the invoking username field is blank which the CopyFail exploit produces after patching /usr/bin/su in the page cache to grant a root shell without a valid caller. A su-to-root record missing its originating user is a strong tampering indicator of the runtime binary modification.

Reporting behind it

Related detections9 linkedT1068 — drag to rearrange

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

Linux sudo CVE-2019-14287 exploit attempt via unusual USER strings

Linux Sudo Privilege Escalation Attempt Matching CVE-2019-14287 Command-Line Pattern

Suspicious Delayed AF_ALG PF_ALG Protocol Registration for CopyFail LPE (via syslog)

Suspicious CrazyHunter BYOVD Driver Drop in Public Directory

Possible Container Escape via Working Directory Under proc CVE-2024-21626

Possible Sudo Heap Overflow Exploitation via sudoedit (CVE-2021-3156)

Suspicious dirty_sock Local Account Artifact From Snapd Privilege Escalation (via process_creation)

Suspicious Modification of Privileged Authentication Binaries via Kernel LPE

Suspicious su to Root with Blank Invoking User for CopyFail LPE (via auth)

Pivot detection · T1068 · 9 related

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