# CVE-2024-26831: net/handshake: Fix handshake_req_destroy_test1

> A race condition in the Linux kernel handshake subsystem caused a use-after-free or null pointer dereference during test cleanup, potentially leading to system instability.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/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:** 17 Apr 2024
- **Updated:** 23 May 2026
- **Also known as:** BELL-CVE-2024-26831, DEBIAN-CVE-2024-26831, GHSA-mmcw-f5qh-65q3, UBUNTU-CVE-2024-26831

## What is CVE-2024-26831?

CVE-2024-26831 is a medium-severity memory corruption vulnerability in Linux kernel, published on 17 Apr 2024. 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:

net/handshake: Fix handshake_req_destroy_test1

Recently, handshake_req_destroy_test1 started failing:

Expected handshake_req_destroy_test == req, but
    handshake_req_destroy_test == 0000000000000000
    req == 0000000060f99b40
not ok 11 req_destroy works

This is because "sock_release(sock)" was replaced with "fput(filp)"
to address a memory leak. Note that sock_release() is synchronous
but fput() usually delays the final close and clean-up.

The delay is not consequential in the other cases that were changed
but handshake_req_destroy_test1 is testing that handshake_req_cancel()
followed by closing the file actually does call the ->hp_destroy
method. Thus the PTR_EQ test at the end has to be sure that the
final close is complete before it checks the pointer.

We cannot use a completion here because if ->hp_destroy is never
called (ie, there is an API bug) then the test will hang.

Reported by: Guenter Roeck <linux@roeck-us.net>

Weakness: CWE-401 (Missing Release of Memory after Effective Lifetime)

## Which versions are affected by CVE-2024-26831?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2024-26831?

Apply the vendor's patch.

## Is CVE-2024-26831 being exploited?

There is no known exploitation of CVE-2024-26831 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2024-26831 and fix it if it is affected.

What it is: CVE-2024-26831 is a medium-severity memory corruption vulnerability in Linux kernel, published on 17 Apr 2024. 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-2024-26831 in the wild and no public exploit code.

Affected product: Linux kernel. 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-2024-26831/ (Markdown: https://insights.sbomify.com/CVE-2024-26831/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-26831
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-26831
- OSV: https://osv.dev/vulnerability/CVE-2024-26831

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-26831/
Summaries are generated and may contain mistakes; the official description above is the record.