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

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 kernel log registration of the PF_ALG protocol family which the CopyFail CVE-2026-31431 exploit triggers by loading the algif_aead module to write controlled bytes into the page cache of setuid binaries. Registration occurring hundreds of seconds after boot rather than at boot time is abnormal and should be correlated with other privilege-escalation signals.

Reporting behind it

Related detections9 linkedT1068 — drag to rearrange

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

Pivot detection · T1068 · 9 related

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.

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