# CVE-2023-28327: Null dereference in Linux

> A local attacker can crash the system or cause denial of service via a NULL pointer dereference in the Linux kernel UNIX protocol.

- **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:** 19 Apr 2023
- **Updated:** 19 Mar 2025
- **Also known as:** AZL-26339, DEBIAN-CVE-2023-28327, GHSA-gpc7-6g78-vfxw, UBUNTU-CVE-2023-28327

## What is CVE-2023-28327?

CVE-2023-28327 is a medium-severity vulnerability in Linux kernel, published on 19 Apr 2023. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A NULL pointer dereference flaw was found in the UNIX protocol in net/unix/diag.c In unix_diag_get_exact in the Linux Kernel. The newly allocated skb does not have sk, leading to a NULL pointer. This flaw allows a local user to crash or potentially cause a denial of service.

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2023-28327?

It affects 2 products.


Products: Linux kernel, Redhat Enterprise Linux.

## How do I fix CVE-2023-28327?

Apply the vendor's patch.

## Is CVE-2023-28327 being exploited?

There is no known exploitation of CVE-2023-28327 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-2023-28327 and fix it if it is affected.

What it is: CVE-2023-28327 is a medium-severity vulnerability in Linux kernel, published on 19 Apr 2023. 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-2023-28327 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-2023-28327/ (Markdown: https://insights.sbomify.com/CVE-2023-28327/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-28327
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-28327
- OSV: https://osv.dev/vulnerability/CVE-2023-28327

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-28327/
Summaries are generated and may contain mistakes; the official description above is the record.