# CVE-2026-7511: wolfSSL improper signature verification in PKCS7_verify

Source: https://junglewise.ai/threats/cve-2026-7511-wolfssl-improper-signature-verification-in-pkcs7-verify  
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-2026-7511 · Severity: info · CVSS 5.9 · Published 2026-06-25

wolfSSL is a security library used to protect data and verify identities in embedded devices and cloud applications. A flaw in how the library verifies digital signatures (PKCS#7) could allow an attacker to trick the system into accepting a forged signature. This could lead to unauthorized access or the acceptance of malicious data as if it were from a trusted source.

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

## Quick answers

**Is CVE-2026-7511 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-7511 being exploited in the wild.

**How severe is CVE-2026-7511?** Informational severity, with a CVSS score of 5.9, published 25 June 2026.

**Which products and versions are affected?** Wolfssl 3.15.5 through 5.9.1.

**Is there a fix for CVE-2026-7511?** A patch was published on 2026-04-24: Fixes merged into master branch Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-7511 attacked?** It is attacked over the network or from the adjacent network, in a software library.

**Am I affected by CVE-2026-7511?** 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

A signer confusion vulnerability exists in wolfSSL's PKCS7_verify function within the wolfcrypt/src/pkcs7.c component. The root cause is improper verification of cryptographic signatures (CWE-347), where the signer associated with a signature is not correctly bound to the signature itself. This flaw permits an attacker to present a forged signature that the library will incorrectly validate as authentic. The vulnerability affects versions 3.15.5 through 5.9.1 and was addressed in the 5.9.1 release via pull request #10203. Exploitation typically requires the attacker to be on the same adjacent network or provide a crafted PKCS#7 payload to an application using the library.

## Affected products

- wolfSSL wolfSSL 3.15.5 through 5.9.1

## Timeline

- 2026-04-13: other: Pull request with fixes submitted to GitHub
- 2026-04-24: patched: Fixes merged into master branch
- 2026-06-25: disclosed: CVE published to NVD

## References

- [https://github.com/wolfSSL/wolfssl](https://github.com/wolfSSL/wolfssl)
- [https://github.com/wolfSSL/wolfssl/pull/10203](https://github.com/wolfSSL/wolfssl/pull/10203)
- [https://www.wolfssl.com/docs/security-vulnerabilities/](https://www.wolfssl.com/docs/security-vulnerabilities/)

## Related threats

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- [wolfSSL MatchTrustedPeer public key validation bypass](https://junglewise.ai/threats/cve-2026-93302-matchtrustedpeer-ignores-the-public-key-used-leading-to-forged-ca)
- [wolfSSL TLS authentication bypass in Raw Public Key handling](https://junglewise.ai/threats/cve-2026-89136-when-using-rpk-raw-public-key-the-client-side-of-a-tls-1-2-1-3)