# CVE-2025-39841: scsi: lpfc: Fix buffer free/clear order in deferred receive path

> A use-after-free vulnerability in the Linux kernel's lpfc driver allows attackers to cause denial of service or execute arbitrary code via concurrent buffer operations.

- **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:** 19 Sep 2025
- **Updated:** 5 Aug 2026
- **Also known as:** AZL-67538, AZL-74829, BELL-CVE-2025-39841, DEBIAN-CVE-2025-39841, GHSA-j8p6-qx4r-877v, ROOT-OS-DEBIAN-11-CVE-2025-39841, ROOT-OS-DEBIAN-12-CVE-2025-39841, ROOT-OS-DEBIAN-13-CVE-2025-39841, ROOT-OS-UBUNTU-2204-CVE-2025-39841, ROOT-OS-UBUNTU-2404-CVE-2025-39841, UBUNTU-CVE-2025-39841

## What is CVE-2025-39841?

CVE-2025-39841 is a critical use after free vulnerability in Debian Debian Linux, published on 19 Sep 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:

scsi: lpfc: Fix buffer free/clear order in deferred receive path

Fix a use-after-free window by correcting the buffer release sequence in
the deferred receive path. The code freed the RQ buffer first and only
then cleared the context pointer under the lock. Concurrent paths (e.g.,
ABTS and the repost path) also inspect and release the same pointer under
the lock, so the old order could lead to double-free/UAF.

Note that the repost path already uses the correct pattern: detach the
pointer under the lock, then free it after dropping the lock. The
deferred path should do the same.

Weakness: CWE-787 (Out-of-bounds Write)

## Which versions are affected by CVE-2025-39841?

It affects 2 products.


Products: Debian Debian Linux, Linux kernel.

## How do I fix CVE-2025-39841?

Apply the vendor's patch.

## Is CVE-2025-39841 being exploited?

There is no known exploitation of CVE-2025-39841 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-2025-39841 and fix it if it is affected.

What it is: CVE-2025-39841 is a critical use after free vulnerability in Debian Debian Linux, published on 19 Sep 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-2025-39841 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-2025-39841/ (Markdown: https://insights.sbomify.com/CVE-2025-39841/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-39841
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-39841
- OSV: https://osv.dev/vulnerability/CVE-2025-39841

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-39841/
Summaries are generated and may contain mistakes; the official description above is the record.