CVE-2026-31528
Description
In the Linux kernel, the following vulnerability has been resolved: perf: Make sure to use pmu_ctx->pmu for groups Oliver reported that x86_pmu_del() ended up doing an out-of-bound memory access when group_sched_in() fails and needs to roll back. This *should* be handled by the transaction callbacks, but he found that when the group leader is a software event, the transaction handlers of the wrong PMU are used. Despite the move_group case in perf_event_open() and group_sched_in() using pmu_ctx->pmu. Turns out, inherit uses event->pmu to clone the events, effectively undoing the move_group case for all inherited contexts. Fix this by also making inherit use pmu_ctx->pmu, ensuring all inherited counters end up in the same pmu context. Similarly, __perf_event_read() should use equally use pmu_ctx->pmu for the group case.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.
✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
OS impact
Linux kernel Affected 2 releases
| Version | Status | Fixed in |
|---|---|---|
| 7.0 | Affected | — |
| — | Affected | 6.6.131 |
SUSE Affected 1 release
| Version | Status | Fixed in |
|---|---|---|
| — | Affected | — |
Debian Fixed 5 releases
| Version | Status | Fixed in |
|---|---|---|
| trixie | Fixed | 6.12.85-1 |
| sid | Fixed | 6.19.11-1 |
| forky | Fixed | 6.19.11-1 |
| bullseye | Fixed | 0 |
| bookworm | Fixed | 0 |
References
- https://git.kernel.org/stable/c/35f7914e54fe7f13654c22ee045b05e4b6d8062b
- https://git.kernel.org/stable/c/3a696e84a8b1fafdd774bb30d62919faf844d9e4
- https://git.kernel.org/stable/c/4b9ce671960627b2505b3f64742544ae9801df97
- https://git.kernel.org/stable/c/4c759446046500a1a6785b25725725c3ff087ace
- https://git.kernel.org/stable/c/656f35b463995bee024d948440128230aacd81e1
- https://www.suse.com/security/cve/CVE-2026-31528.html
- https://security-tracker.debian.org/tracker/CVE-2026-31528
CWEs
CWE-125
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.