CVE-2026-97960 perf/x86/intel: Prevent drain_pebs() reentry
A race condition in the Linux kernel's Intel PEBS handling allows local attackers to trigger out-of-bounds memory access, potentially leading to privilege escalation or code execution.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-97960?
CVE-2026-97960 is a vulnerability in Linux, published on 25 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
perf/x86/intel: Prevent drain_pebs() reentry
The PEBS buffer is shared by all events on a CPU, so drain_pebs() must not be reentered. If so, one instance may observe stale buffer state and potentially access out-of-bound memory.
Most invocations happen in NMI context, which naturally prevents reentry. However, drain_pebs() is also reachable from process context via intel_pmu_drain_pebs_buffer().
In those paths, the PMU is often already disabled, but not guaranteed. For example, __intel_pmu_pebs_disable() only disables the target counter, so other active counters can still raise a PMI and interrupt an in-flight drain_pebs(). Here is an example,
__perf_addr_filters_adjust() perf_event_stop() __perf_event_stop() x86_pmu_stop() (event->pmu->stop) intel_pmu_disable_event() intel_pmu_pebs_disable() __intel_pmu_pebs_disable() intel_pmu_drain_large_pebs() intel_pmu_drain_pebs_buffer()
Introduce __intel_pmu_quiesce() and __intel_pmu_resume() helpers and use them in intel_pmu_drain_large_pebs() to disable the full PMU around the intel_pmu_drain_pebs_buffer() call, preventing reentry.
Also add a warning in intel_pmu_drain_pebs_buffer() when the full PMU is not disabled.
Which versions are affected by CVE-2026-97960?
How do I fix CVE-2026-97960?
Apply the vendor's patch.
Is CVE-2026-97960 being exploited?
There is no known exploitation of CVE-2026-97960 in the wild and no public exploit code.
Sources
Also known as AZL-104360, BELL-CVE-2026-97960, DEBIAN-CVE-2026-97960, GHSA-5xpp-w3qp-6w34, UBUNTU-CVE-2026-97960.