# CVE-2023-54269: SUNRPC: double free xprt_ctxt while still in use

> A double free vulnerability in the Linux kernel SUNRPC subsystem allows attackers to cause a denial of service via crafted RPC requests.

- **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:** 30 Dec 2025
- **Updated:** 15 Oct 2026
- **Also known as:** BELL-CVE-2023-54269, DEBIAN-CVE-2023-54269, GHSA-cphq-rv4m-x79g, UBUNTU-CVE-2023-54269

## What is CVE-2023-54269?

CVE-2023-54269 is a critical use after free vulnerability in Linux, published on 30 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:

SUNRPC: double free xprt_ctxt while still in use

When an RPC request is deferred, the rq_xprt_ctxt pointer is moved out
of the svc_rqst into the svc_deferred_req.
When the deferred request is revisited, the pointer is copied into
the new svc_rqst - and also remains in the svc_deferred_req.

In the (rare?) case that the request is deferred a second time, the old
svc_deferred_req is reused - it still has all the correct content.
However in that case the rq_xprt_ctxt pointer is NOT cleared so that
when xpo_release_xprt is called, the ctxt is freed (UDP) or possible
added to a free list (RDMA).
When the deferred request is revisited for a second time, it will
reference this ctxt which may be invalid, and the free the object a
second time which is likely to oops.

So change svc_defer() to *always* clear rq_xprt_ctxt, and assert that
the value is now stored in the svc_deferred_req.

## Which versions are affected by CVE-2023-54269?


## How do I fix CVE-2023-54269?

Apply the vendor's patch.

## Is CVE-2023-54269 being exploited?

There is no known exploitation of CVE-2023-54269 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-54269 and fix it if it is affected.

What it is: CVE-2023-54269 is a critical use after free vulnerability in Linux, published on 30 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-2023-54269 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-2023-54269/ (Markdown: https://insights.sbomify.com/CVE-2023-54269/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-54269
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-54269
- OSV: https://osv.dev/vulnerability/CVE-2023-54269

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-54269/
Summaries are generated and may contain mistakes; the official description above is the record.