# 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.

- **Severity:** Not scored
- **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:** Yes
- **Published:** 24 Dec 2025
- **Updated:** 11 May 2026
- **Also known as:** BELL-CVE-2025-68375, DEBIAN-CVE-2025-68375, GHSA-f66w-mcmh-g56g, UBUNTU-CVE-2025-68375

## 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.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-68375 and fix it if it is affected.

What it is: 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.
Exploitation: There is no known exploitation of CVE-2025-68375 in the wild and no public exploit code.

Affected product: Linux. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2025-68375/ (Markdown: https://insights.sbomify.com/CVE-2025-68375/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-68375
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-68375
- OSV: https://osv.dev/vulnerability/CVE-2025-68375

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-68375/
Summaries are generated and may contain mistakes; the official description above is the record.