# CVE-2026-80520: ovpn: fix NULL dereference when killing missing key

> A NULL pointer dereference in the Linux kernel's ovpn module allows a remote attacker to cause a denial of service by triggering a specific key removal path.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/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:** 26 Aug 2026
- **Updated:** 27 Aug 2026
- **Also known as:** BELL-CVE-2026-80520, DEBIAN-CVE-2026-80520, GHSA-v79r-cp4c-r8xr, UBUNTU-CVE-2026-80520

## What is CVE-2026-80520?

CVE-2026-80520 is a high-severity vulnerability in Linux, published on 26 Aug 2026. 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:

ovpn: fix NULL dereference when killing missing key

ovpn_crypto_kill_key assumes both crypto slots are populated and
dereferences each slot before checking it. That is not guaranteed: a
peer can have only one installed key, and the kill path may be asked to
remove a key that is not present.

Read each slot once while holding the crypto state lock, check for NULL
before looking at key_id, and only replace the slot that actually
matches.

## Which versions are affected by CVE-2026-80520?


## How do I fix CVE-2026-80520?

Apply the vendor's patch.

## Is CVE-2026-80520 being exploited?

There is no known exploitation of CVE-2026-80520 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-80520 and fix it if it is affected.

What it is: CVE-2026-80520 is a high-severity vulnerability in Linux, published on 26 Aug 2026. 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-2026-80520 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-2026-80520/ (Markdown: https://insights.sbomify.com/CVE-2026-80520/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-80520
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-80520
- OSV: https://osv.dev/vulnerability/CVE-2026-80520

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-80520/
Summaries are generated and may contain mistakes; the official description above is the record.