CVE-2025-68375 perf/x86: Fix NULL event access and potential PEBS record loss
A local attacker can trigger a NULL pointer dereference in the Linux kernel's perf subsystem, causing a system crash or denial of service.
- 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-2025-68375?
CVE-2025-68375 is a vulnerability in Linux, published on 24 Dec 2025. 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: Fix NULL event access and potential PEBS record loss
When intel_pmu_drain_pebs_icl() is called to drain PEBS records, the perf_event_overflow() could be called to process the last PEBS record.
While perf_event_overflow() could trigger the interrupt throttle and stop all events of the group, like what the below call-chain shows.
perf_event_overflow() -> __perf_event_overflow() ->__perf_event_account_interrupt() -> perf_event_throttle_group() -> perf_event_throttle() -> event->pmu->stop() -> x86_pmu_stop()
The side effect of stopping the events is that all corresponding event pointers in cpuc->events[] array are cleared to NULL.
Assume there are two PEBS events (event a and event b) in a group. When intel_pmu_drain_pebs_icl() calls perf_event_overflow() to process the last PEBS record of PEBS event a, interrupt throttle is triggered and all pointers of event a and event b are cleared to NULL. Then intel_pmu_drain_pebs_icl() tries to process the last PEBS record of event b and encounters NULL pointer access.
To avoid this issue, move cpuc->events[] clearing from x86_pmu_stop() to x86_pmu_del(). It's safe since cpuc->active_mask or cpuc->pebs_enabled is always checked before access the event pointer from cpuc->events[].
Which versions are affected by CVE-2025-68375?
How do I fix CVE-2025-68375?
Apply the vendor's patch.
Is CVE-2025-68375 being exploited?
There is no known exploitation of CVE-2025-68375 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2025-68375, DEBIAN-CVE-2025-68375, GHSA-f66w-mcmh-g56g, UBUNTU-CVE-2025-68375.