# CVE-2008-1949: Null dereference in n/a

> Remote attackers can cause a denial of service via NULL dereference by sending multiple Client Hello messages in a single TLS packet.

- **Severity:** Critical 9.3 (`AV:N/AC:M/Au:N/C:C/I:C/A:C`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 21 May 2008
- **Updated:** 7 Aug 2024
- **Also known as:** GHSA-5mrf-xh4h-r8wx

## What is CVE-2008-1949?

CVE-2008-1949 is a critical vulnerability in Gnu Gnutls, published on 21 May 2008. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

The _gnutls_recv_client_kx_message function in lib/gnutls_kx.c in libgnutls in gnutls-serv in GnuTLS before 2.2.4 continues to process Client Hello messages within a TLS message after one has already been processed, which allows remote attackers to cause a denial of service (NULL dereference and crash) via a TLS message containing multiple Client Hello messages, aka GNUTLS-SA-2008-1-2.

Weakness: CWE-287 (Improper Authentication)

## Which versions are affected by CVE-2008-1949?

It affects 1 product.


Products: Gnu Gnutls.

## How do I fix CVE-2008-1949?

Upgrade to a fixed version.

## Is CVE-2008-1949 being exploited?

There is no known exploitation of CVE-2008-1949 in the wild and no public exploit code.

## Other vulnerabilities in Gnu Gnutls

- [CVE-2008-1948](https://insights.sbomify.com/CVE-2008-1948/): Memory corruption in n/a (critical 10.0)
- [CVE-2017-5334](https://insights.sbomify.com/CVE-2017-5334/): Use after free in n/a (critical 9.8)
- [CVE-2017-5336](https://insights.sbomify.com/CVE-2017-5336/): Memory corruption in n/a (critical 9.8)
- [CVE-2017-5337](https://insights.sbomify.com/CVE-2017-5337/): Memory corruption in n/a (critical 9.8)
- [CVE-2004-2531](https://insights.sbomify.com/CVE-2004-2531/): Denial of service in n/a (high 7.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2008-1949 and fix it if it is affected.

What it is: CVE-2008-1949 is a critical vulnerability in Gnu Gnutls, published on 21 May 2008. 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-2008-1949 in the wild and no public exploit code.

Affected product: Gnu Gnutls. 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-2008-1949/ (Markdown: https://insights.sbomify.com/CVE-2008-1949/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2008-1949
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2008-1949
- OSV: https://osv.dev/vulnerability/CVE-2008-1949

---
From sbomify Insights: https://insights.sbomify.com/CVE-2008-1949/
Summaries are generated and may contain mistakes; the official description above is the record.