# CVE-2024-11738: Rustls: rustls network-reachable panic in `acceptor::accept`

> A remote attacker can cause a denial of service by sending a fragmented TLS ClientHello message to applications using the Rustls library.

- **Severity:** Medium 5.3 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 6 Dec 2024
- **Updated:** 20 Nov 2025
- **Also known as:** AZL-61546, CVE-2024-58254, GHSA-qg5g-gv98-5ffh, RUSTSEC-2024-0399, UBUNTU-CVE-2024-11738, openSUSE-SU-2024:14539-1

## What is CVE-2024-11738?

CVE-2024-11738 is a medium-severity denial of service vulnerability in Red Hat Trusted Artifact Signer, published on 6 Dec 2024. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A flaw was found in Rustls 0.23.13 and related APIs. This vulnerability allows denial of service (panic) via a fragmented TLS ClientHello message.

Weakness: CWE-248 (Uncaught Exception)

## Which versions are affected by CVE-2024-11738?

3 open source packages ship an affected version, including rustls. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `rustls` | crates.io | From 0.23.0 | 0.23.0, 0.23.18 |
| `rustls` | crates.io | From 0.23.13 | 0.23.18 |
| `rustls` | crates.io | From 0.23.13 | 0.23.18 |
| `himmelblau` | openSUSE:Tumbleweed | All versions | 0.7.7+git.0.b48d0bb-1.1 |

Products: Rustls Project Rustls.

## How do I fix CVE-2024-11738?

Upgrade rustls to a fixed version for your release line: 0.23.0 or 0.23.18.

## Is CVE-2024-11738 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2024-11738 exists.

## Other vulnerabilities in Red Hat Trusted Artifact Signer

- [CVE-2019-15541](https://insights.sbomify.com/CVE-2019-15541/): Denial of service in n/a (high 7.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2024-11738 and fix it if it is affected.

What it is: CVE-2024-11738 is a medium-severity denial of service vulnerability in Red Hat Trusted Artifact Signer, published on 6 Dec 2024. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2024-11738 exists.

Affected packages and fixed versions:
- rustls (crates.io): affected from 0.23.0; fixed in 0.23.0, 0.23.18
- rustls (crates.io): affected from 0.23.13; fixed in 0.23.18
- rustls (crates.io): affected from 0.23.13; fixed in 0.23.18

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-2024-11738/ (Markdown: https://insights.sbomify.com/CVE-2024-11738/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-11738
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-11738
- OSV: https://osv.dev/vulnerability/CVE-2024-11738

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-11738/
Summaries are generated and may contain mistakes; the official description above is the record.