CVE-2026-74753

Technical Description

In the Linux kernel, the following vulnerability has been resolved:

perf: Reject exited events as group leaders

perf_event_remove_on_exec() sets remove-on-exec events to the EXIT state

and detaches their group relationships. The event's file descriptor can

remain open, however, and perf_event_open() currently accepts that event

as a group leader because its early validation rejects only REVOKED and

DEAD events.

A new sibling can consequently be linked to the detached leader. When

the leader is closed, perf_group_detach() observes that its

PERF_ATTACH_GROUP bit is already clear and skips the new sibling. The

sibling then retains a group_leader pointer to the freed event.

Reject group leaders in the EXIT state. Perform the check while holding

the shared context mutex so that an exec in the target task cannot detach

the leader between validation and group attachment.

[peterz: make the earlier test fully consistent]

Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

References