# CVE-2024-5991: Buffer overread in domain name matching

> An attacker can cause a buffer overread in wolfSSL's domain name matching, potentially leading to crashes or information disclosure.

- **Severity:** Critical 10.0 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 27 Aug 2024
- **Updated:** 27 Aug 2024
- **Also known as:** AZL-48342, AZL-48368, DEBIAN-CVE-2024-5991, GHSA-jwjf-h4v6-qrpp, JLSEC-2026-685, UBUNTU-CVE-2024-5991

## What is CVE-2024-5991?

CVE-2024-5991 is a critical memory corruption vulnerability in Wolfssl Wolfssl, published on 27 Aug 2024. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

In function MatchDomainName(), input param str is treated as a NULL terminated string despite being user provided and unchecked. Specifically, the function X509_check_host() takes in a pointer and length to check against, with no requirements that it be NULL terminated. If a caller was attempting to do a name check on a non-NULL terminated buffer, the code would read beyond the bounds of the input array until it found a NULL terminator.This issue affects wolfSSL: through 5.7.0.

Weakness: CWE-125 (Out-of-bounds Read)

## Which versions are affected by CVE-2024-5991?

It affects 1 product.


Products: Wolfssl Wolfssl.

## How do I fix CVE-2024-5991?

Upgrade to a fixed version.

## Is CVE-2024-5991 being exploited?

There is no known exploitation of CVE-2024-5991 in the wild and no public exploit code.

## Other vulnerabilities in Wolfssl Wolfssl

- [CVE-2021-37155](https://insights.sbomify.com/CVE-2021-37155/): Security feature bypass in n/a (critical 9.8)
- [CVE-2020-36177](https://insights.sbomify.com/CVE-2020-36177/): Memory corruption in n/a (critical 9.8)
- [CVE-2014-2896](https://insights.sbomify.com/CVE-2014-2896/): Memory corruption in n/a (critical 9.8)
- [CVE-2014-2897](https://insights.sbomify.com/CVE-2014-2897/): Memory corruption in n/a (critical 9.8)
- [CVE-2014-2898](https://insights.sbomify.com/CVE-2014-2898/): Information disclosure in n/a (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2024-5991 and fix it if it is affected.

What it is: CVE-2024-5991 is a critical memory corruption vulnerability in Wolfssl Wolfssl, published on 27 Aug 2024. 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-2024-5991 in the wild and no public exploit code.

Affected product: Wolfssl Wolfssl. 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-2024-5991/ (Markdown: https://insights.sbomify.com/CVE-2024-5991/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-5991
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-5991
- OSV: https://osv.dev/vulnerability/CVE-2024-5991

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-5991/
Summaries are generated and may contain mistakes; the official description above is the record.