# CVE-2025-38424: perf: Fix sample vs do_exit()

> A race condition in the Linux kernel perf subsystem allows a local attacker to cause a system crash by triggering a use-after-free during process exit.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **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:** 25 Jul 2025
- **Updated:** 15 Oct 2026
- **Also known as:** BELL-CVE-2025-38424, DEBIAN-CVE-2025-38424, GHSA-6p9w-8r99-f39c, OESA-2025-1962, ROOT-OS-DEBIAN-11-CVE-2025-38424, ROOT-OS-DEBIAN-12-CVE-2025-38424, ROOT-OS-UBUNTU-2204-CVE-2025-38424, ROOT-OS-UBUNTU-2404-CVE-2025-38424, UBUNTU-CVE-2025-38424

## What is CVE-2025-38424?

CVE-2025-38424 is a high-severity vulnerability in Debian Debian Linux, published on 25 Jul 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: Fix sample vs do_exit()

Baisheng Gao reported an ARM64 crash, which Mark decoded as being a
synchronous external abort -- most likely due to trying to access
MMIO in bad ways.

The crash further shows perf trying to do a user stack sample while in
exit_mmap()'s tlb_finish_mmu() -- i.e. while tearing down the address
space it is trying to access.

It turns out that we stop perf after we tear down the userspace mm; a
receipie for disaster, since perf likes to access userspace for
various reasons.

Flip this order by moving up where we stop perf in do_exit().

Additionally, harden PERF_SAMPLE_CALLCHAIN and PERF_SAMPLE_STACK_USER
to abort when the current task does not have an mm (exit_mm() makes
sure to set current->mm = NULL; before commencing with the actual
teardown). Such that CPU wide events don't trip on this same problem.

## Which versions are affected by CVE-2025-38424?

It affects 2 products.


Products: Debian Debian Linux, Linux kernel.

## How do I fix CVE-2025-38424?

Apply the vendor's patch.

## Is CVE-2025-38424 being exploited?

There is no known exploitation of CVE-2025-38424 in the wild and no public exploit code.

## Other vulnerabilities in Debian Debian Linux

- [CVE-2015-3306](https://insights.sbomify.com/CVE-2015-3306/): ProFTPD Improper Access Control (critical 10.0, exploited in the wild)
- [CVE-2025-49113](https://insights.sbomify.com/CVE-2025-49113/): RoundCube Webmail Deserialization of Untrusted Data (critical 9.9, exploited in the wild)
- [CVE-2026-24061](https://insights.sbomify.com/CVE-2026-24061/): GNU InetUtils Argument Injection (critical 9.8, exploited in the wild)
- [CVE-2025-39682](https://insights.sbomify.com/CVE-2025-39682/): Linux Kernel Improper Check for Unusual or Exceptional Conditions (critical 9.8, exploited in the wild)
- [CVE-2024-9680](https://insights.sbomify.com/CVE-2024-9680/): Mozilla Firefox Use-After-Free (critical 9.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-38424 and fix it if it is affected.

What it is: CVE-2025-38424 is a high-severity vulnerability in Debian Debian Linux, published on 25 Jul 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-2025-38424 in the wild and no public exploit code.

Affected product: Debian Debian 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-2025-38424/ (Markdown: https://insights.sbomify.com/CVE-2025-38424/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-38424
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-38424
- OSV: https://osv.dev/vulnerability/CVE-2025-38424

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-38424/
Summaries are generated and may contain mistakes; the official description above is the record.