# CVE-2026-6325: wolfSSL out-of-bounds write in SetSuitesHashSigAlgo

Source: https://junglewise.ai/threats/cve-2026-6325-wolfssl-out-of-bounds-write-in-setsuiteshashsigalgo  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-06-25. Updated: 2026-06-25  
License: CC BY 4.0 with a link back

CVE-2026-6325 · Severity: info · CVSS 2 · Published 2026-06-25

wolfSSL is a security library used to provide encrypted communications for embedded devices and cloud applications. A technical flaw in how the library handles lists of digital signature algorithms could allow a local attacker to cause a memory error. While the risk is low, this could potentially lead to a service crash or limited unauthorized memory modification during the secure connection process.

Technologies: [Wolfssl](https://junglewise.ai/threats/technologies/wolfssl). Vendors: [Wolfssl](https://junglewise.ai/threats/vendors/wolfssl).

## Quick answers

**Is CVE-2026-6325 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-6325 being exploited in the wild.

**How severe is CVE-2026-6325?** Informational severity, with a CVSS score of 2, published 25 June 2026.

**Which products and versions are affected?** Wolfssl 4.8.0 to 5.9.1.

**Is there a fix for CVE-2026-6325?** A patch was published on 2026-04-15: Fix merged into master branch Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-6325 attacked?** It is attacked with local access, in a software library.

**Am I affected by CVE-2026-6325?** Check whether you run Wolfssl at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

An out-of-bounds write vulnerability exists in the `SetSuitesHashSigAlgo` function within `src/internal.c`. The issue stems from a lack of preflight bounds checking when parsing user-provided signature algorithm lists, specifically when handling RSA-PSS in TLS 1.3 which adds multiple entries to the list. An attacker providing a specially crafted, oversized list can trigger a write past the destination buffer's boundaries. This vulnerability requires the application to be configured with specific options like `--enable-opensslextra` and involves local interaction. A fix was introduced in the wolfSSL master branch to add explicit bounds checks before calling `AddSuiteHashSigAlgo`.

## Affected products

- wolfSSL wolfSSL 4.8.0 to 5.9.1

## Timeline

- 2026-04-13: other: Pull request submitted to wolfSSL repository
- 2026-04-15: patched: Fix merged into master branch
- 2026-06-25: advisory: NVD publication date

## References

- [https://github.com/wolfSSL/wolfssl](https://github.com/wolfSSL/wolfssl)
- [https://github.com/wolfSSL/wolfssl/pull/10204](https://github.com/wolfSSL/wolfssl/pull/10204)
- [https://www.wolfssl.com/docs/security-vulnerabilities/](https://www.wolfssl.com/docs/security-vulnerabilities/)

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