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

CVE-2022-39173 is fixed in wolfssl on 1 platform, first by DEBIAN-CVE-2022-39173, released September 29, 2022. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2022-39173
- Priority: High
- CVSS: 7.5 (high)
- EPSS: 0.0576
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Sep 29, 2022

## 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.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | wolfssl Debian 12.15 (bookworm) | 5.5.3-1 | [DEBIAN-CVE-2022-39173](https://patchblox.com/security/data/fix/linux/debian-cve-2022-39173.md) | Sep 29, 2022 |
| Linux | wolfssl Debian 13.5 (trixie) | 5.5.3-1 | [DEBIAN-CVE-2022-39173](https://patchblox.com/security/data/fix/linux/debian-cve-2022-39173.md) | Sep 29, 2022 |

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Data as of 2026-11-08T13:06:02Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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