# CVE-2025-13034: No QUIC certificate pinning with GnuTLS

> Attackers can bypass certificate pinning in curl when using QUIC with GnuTLS and disabled verification, allowing man-in-the-middle attacks.

- **Severity:** Medium 5.9 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 8 Jan 2026
- **Updated:** 15 Sep 2026
- **Also known as:** ALPINE-CVE-2025-13034, CURL-CVE-2025-13034, DEBIAN-CVE-2025-13034, GHSA-9r76-qj98-jfhc, JLSEC-2026-426, MINI-c73v-v84q-fmgc, UBUNTU-CVE-2025-13034

## What is CVE-2025-13034?

CVE-2025-13034 is a medium-severity vulnerability in Haxx Curl, published on 8 Jan 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

When using `CURLOPT_PINNEDPUBLICKEY` option with libcurl or `--pinnedpubkey`
with the curl tool, curl should check the public key of the server certificate
to verify the peer.

This check was skipped in a certain condition that would then make curl allow
the connection without performing the proper check, thus not noticing a
possible impostor. To skip this check, the connection had to be done with QUIC
with ngtcp2 built to use GnuTLS and the user had to explicitly disable the
standard certificate verification.

Weakness: CWE-295 (Improper Certificate Validation)

## Which versions are affected by CVE-2025-13034?

It affects 1 product.


Products: Haxx Curl.

## How do I fix CVE-2025-13034?

Apply the vendor's patch.

## Is CVE-2025-13034 being exploited?

There is no known exploitation of CVE-2025-13034 in the wild and no public exploit code.

## Other vulnerabilities in Haxx Curl

- [CVE-2026-19931](https://insights.sbomify.com/CVE-2026-19931/): Negotiate ambient user conn reuse (critical 9.8)
- [CVE-2026-10536](https://insights.sbomify.com/CVE-2026-10536/): HTTP/2 stream-dependency tree UAF (critical 9.8)
- [CVE-2026-11856](https://insights.sbomify.com/CVE-2026-11856/): cross-origin Digest auth state leak (critical 9.8)
- [CVE-2026-8925](https://insights.sbomify.com/CVE-2026-8925/): SASL double-free (critical 9.8)
- [CVE-2026-9079](https://insights.sbomify.com/CVE-2026-9079/): stale proxy password leak (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-13034 and fix it if it is affected.

What it is: CVE-2025-13034 is a medium-severity vulnerability in Haxx Curl, published on 8 Jan 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-2025-13034 in the wild and no public exploit code.

Affected product: Haxx Curl. 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-2025-13034/ (Markdown: https://insights.sbomify.com/CVE-2025-13034/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-13034
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-13034
- OSV: https://osv.dev/vulnerability/CVE-2025-13034

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-13034/
Summaries are generated and may contain mistakes; the official description above is the record.