CVE-2026-64556

Name of the Vulnerable Software and Affected Versions Linux kernel (affected versions not specified)

Description An issue exists in the perf/core component where the perf event remove on exec() function removes events by calling perf event exit event(). For top-level events, this process only uses DETACH EXIT, which can lead to an inconsistent group state if the removed event is a group leader and contains siblings that do not have remove on exec. In such cases, surviving siblings may remain active and attached to the removed leader's sibling list while lacking a valid group leader on the PMU (Performance Monitoring Unit) context active lists. A subsequent close of the removed leader using DETACH GROUP can promote these active siblings from the stale state, causing the next schedule-in to add an already-linked active list entry again, which corrupts the PMU context active list. This condition is detectable as a list add double-add in the merge sched in() function when DEBUG LIST is enabled.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.