# CVE-2023-53426: xsk: Fix xsk_diag use-after-free error during socket cleanup

> A use-after-free in the Linux kernel's xsk_diag interface allows attackers to potentially execute code or escalate privileges during socket cleanup.

- **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:** 18 Sep 2025
- **Updated:** 5 Aug 2026
- **Also known as:** BELL-CVE-2023-53426, DEBIAN-CVE-2023-53426, GHSA-26wc-246g-r3wf, UBUNTU-CVE-2023-53426

## What is CVE-2023-53426?

CVE-2023-53426 is a high-severity use after free vulnerability in Linux kernel, published on 18 Sep 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:

xsk: Fix xsk_diag use-after-free error during socket cleanup

Fix a use-after-free error that is possible if the xsk_diag interface
is used after the socket has been unbound from the device. This can
happen either due to the socket being closed or the device
disappearing. In the early days of AF_XDP, the way we tested that a
socket was not bound to a device was to simply check if the netdevice
pointer in the xsk socket structure was NULL. Later, a better system
was introduced by having an explicit state variable in the xsk socket
struct. For example, the state of a socket that is on the way to being
closed and has been unbound from the device is XSK_UNBOUND.

The commit in the Fixes tag below deleted the old way of signalling
that a socket is unbound, setting dev to NULL. This in the belief that
all code using the old way had been exterminated. That was
unfortunately not true as the xsk diagnostics code was still using the
old way and thus does not work as intended when a socket is going
down. Fix this by introducing a test against the state variable. If
the socket is in the state XSK_UNBOUND, simply abort the diagnostic's
netlink operation.

Weakness: CWE-416 (Use After Free)

## Which versions are affected by CVE-2023-53426?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2023-53426?

Apply the vendor's patch.

## Is CVE-2023-53426 being exploited?

There is no known exploitation of CVE-2023-53426 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-2023-53426 and fix it if it is affected.

What it is: CVE-2023-53426 is a high-severity use after free vulnerability in Linux kernel, published on 18 Sep 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-2023-53426 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-2023-53426/ (Markdown: https://insights.sbomify.com/CVE-2023-53426/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-53426
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-53426
- OSV: https://osv.dev/vulnerability/CVE-2023-53426

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-53426/
Summaries are generated and may contain mistakes; the official description above is the record.