# CVE-2023-53867: ceph: fix potential use-after-free bug when trimming caps

> A use-after-free vulnerability in the Linux kernel's Ceph filesystem allows attackers to cause a crash or potentially execute code via race conditions during cap trimming.

- **Severity:** Critical 9.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 24 Dec 2025
- **Updated:** 15 Oct 2026
- **Also known as:** BELL-CVE-2023-53867, DEBIAN-CVE-2023-53867, GHSA-f688-j3hq-jm53, ROOT-OS-DEBIAN-11-CVE-2023-53867, ROOT-OS-UBUNTU-2204-CVE-2023-53867, UBUNTU-CVE-2023-53867

## What is CVE-2023-53867?

CVE-2023-53867 is a critical use after free vulnerability in Linux, published on 24 Dec 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

In the Linux kernel, the following vulnerability has been resolved:

ceph: fix potential use-after-free bug when trimming caps

When trimming the caps and just after the 'session->s_cap_lock' is
released in ceph_iterate_session_caps() the cap maybe removed by
another thread, and when using the stale cap memory in the callbacks
it will trigger use-after-free crash.

We need to check the existence of the cap just after the 'ci->i_ceph_lock'
being acquired. And do nothing if it's already removed.

## Which versions are affected by CVE-2023-53867?


## How do I fix CVE-2023-53867?

Apply the vendor's patch.

## Is CVE-2023-53867 being exploited?

There is no known exploitation of CVE-2023-53867 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-53867 and fix it if it is affected.

What it is: CVE-2023-53867 is a critical use after free vulnerability in Linux, published on 24 Dec 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2023-53867 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-2023-53867/ (Markdown: https://insights.sbomify.com/CVE-2023-53867/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-53867
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-53867
- OSV: https://osv.dev/vulnerability/CVE-2023-53867

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-53867/
Summaries are generated and may contain mistakes; the official description above is the record.