# CVE-2026-5260: Gnutls: gnutls: information disclosure via heap overread in rsa key exchange

> A remote attacker can trigger a heap overread in GnuTLS during RSA key exchange with PKCS#11 tokens, leading to information disclosure.

- **Severity:** High 8.2 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/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 May 2026
- **Updated:** 29 Oct 2026
- **Also known as:** ALPINE-CVE-2026-5260, AZL-89184, BELL-CVE-2026-5260, DEBIAN-CVE-2026-5260, ECHO-f2e1-886c-4323, GHSA-6hj5-4cv5-f46x

## What is CVE-2026-5260?

CVE-2026-5260 is a high-severity vulnerability in Cert Manager support for Red Hat OpenShift release 1.17, published on 26 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A flaw was found in libgnutls. A remote attacker, by sending an extremely short premaster secret during an RSA key exchange to a server using an RSA key backed by a PKCS#11 token, could trigger a short heap overread. This memory corruption vulnerability could lead to information disclosure.

Weakness: CWE-126 (Buffer Over-read)

## Which versions are affected by CVE-2026-5260?


## How do I fix CVE-2026-5260?

Apply the vendor's patch.

## Is CVE-2026-5260 being exploited?

There is no known exploitation of CVE-2026-5260 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-5260 and fix it if it is affected.

What it is: CVE-2026-5260 is a high-severity vulnerability in Cert Manager support for Red Hat OpenShift release 1.17, published on 26 May 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-2026-5260 in the wild and no public exploit code.

Affected product: Cert Manager support for Red Hat OpenShift release 1.17. 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-2026-5260/ (Markdown: https://insights.sbomify.com/CVE-2026-5260/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-5260
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-5260
- OSV: https://osv.dev/vulnerability/CVE-2026-5260

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-5260/
Summaries are generated and may contain mistakes; the official description above is the record.