# CVE-2026-3230: Improper key_share validation in TLS 1.3 HelloRetryRequest

> Attackers can compromise TLS confidentiality by exploiting missing key_share validation in wolfSSL's HelloRetryRequest handling, leading to predictable traffic secrets.

- **Severity:** Low 1.2 (`CVSS:4.0/AV:N/AC:H/AT:P/PR:H/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:P/AU:Y/R:A/V:D/U:Clear`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 19 Mar 2026
- **Updated:** 20 Mar 2026
- **Also known as:** DEBIAN-CVE-2026-3230, GHSA-g3xr-5f55-cf5g, JLSEC-2026-704, UBUNTU-CVE-2026-3230

## What is CVE-2026-3230?

CVE-2026-3230 is a low-severity vulnerability in Wolfssl Wolfssl, published on 19 Mar 2026. An attacker needs administrator access to exploit it, with no action from the victim.

### Official description

Missing required cryptographic step in the TLS 1.3 client HelloRetryRequest handshake logic in wolfSSL could lead to a compromise in the confidentiality of TLS-protected communications via a crafted HelloRetryRequest followed by a ServerHello message that omits the required key_share extension, resulting in derivation of predictable traffic secrets from (EC)DHE shared secret. This issue does not affect the client's authentication of the server during TLS handshakes.

Weakness: CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2026-3230?

It affects 1 product.


Products: Wolfssl Wolfssl.

## How do I fix CVE-2026-3230?

Apply the vendor's patch.

## Is CVE-2026-3230 being exploited?

There is no known exploitation of CVE-2026-3230 in the wild and no public exploit code.

## 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-2026-3230 and fix it if it is affected.

What it is: CVE-2026-3230 is a low-severity vulnerability in Wolfssl Wolfssl, published on 19 Mar 2026. An attacker needs administrator access to exploit it, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-3230 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-2026-3230/ (Markdown: https://insights.sbomify.com/CVE-2026-3230/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-3230
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-3230
- OSV: https://osv.dev/vulnerability/CVE-2026-3230

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-3230/
Summaries are generated and may contain mistakes; the official description above is the record.