# CVE-2022-39173: In wolfSSL before 5.5.1, malicious clients can cause a buffer overflow during a TLS 1.3 handshake.


- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Fix available:** Yes
- **Published:** 29 Sep 2022
- **Updated:** 20 May 2025
- **Also known as:** DEBIAN-CVE-2022-39173, GHSA-ww6v-6x26-hgfc, JLSEC-2026-673, UBUNTU-CVE-2022-39173

## What is CVE-2022-39173?

CVE-2022-39173 is a high-severity vulnerability in Wolfssl Wolfssl, published on 29 Sep 2022. 

### Official description

In wolfSSL before 5.5.1, malicious clients can cause a buffer overflow during a TLS 1.3 handshake. This occurs when an attacker supposedly resumes a previous TLS session. During the resumption Client Hello a Hello Retry Request must be triggered. Both Client Hellos are required to contain a list of duplicate cipher suites to trigger the buffer overflow. In total, two Client Hellos have to be sent: one in the resumed session, and a second one as a response to a Hello Retry Request message.

Weakness: CWE-787 (Out-of-bounds Write)

## Which versions are affected by CVE-2022-39173?

It affects 1 product.


Products: Wolfssl Wolfssl.

## How do I fix CVE-2022-39173?

Upgrade to a fixed version.

## Is CVE-2022-39173 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2022-39173 exists.

## Other vulnerabilities in Wolfssl Wolfssl

- [CVE-2024-5991](https://insights.sbomify.com/CVE-2024-5991/): Buffer overread in domain name matching (critical 10.0)
- [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)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2022-39173 and fix it if it is affected.

What it is: CVE-2022-39173 is a high-severity vulnerability in Wolfssl Wolfssl, published on 29 Sep 2022. 
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2022-39173 exists.

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-2022-39173/ (Markdown: https://insights.sbomify.com/CVE-2022-39173/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2022-39173
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2022-39173
- OSV: https://osv.dev/vulnerability/CVE-2022-39173

---
From sbomify Insights: https://insights.sbomify.com/CVE-2022-39173/
Summaries are generated and may contain mistakes; the official description above is the record.