wolfSSL Flaw Could Allow Forged Certificates to Be Accepted
Summary
CVE-2026-5194 lets vulnerable wolfSSL builds accept undersized digests during signature verification, potentially allowing forged certificates to be trusted. wolfSSL fixed the flaw in version 5.9.1.
Key points
- The flaw affects wolfSSL signature verification, which can accept digests smaller than appropriate for the signature or key type.
- Affected algorithms include ECDSA/ECC, DSA, ML-DSA, Ed25519, and Ed448.
- An attacker could potentially use a forged certificate to make a vulnerable application or device trust a malicious server, file, or connection.
- wolfSSL fixed CVE-2026-5194 in version 5.9.1, released April 8.
- The advisory notes that exploitation may depend on deployment-specific conditions.
- Administrators using distribution packages, vendor firmware, or embedded SDKs should check downstream advisories and update affected deployments.
Article Details
- Vulnerability Types
- Cryptographic validation flaw: wolfSSL may accept undersized hash digests during certificate signature verification.
- Severity
- Critical
- Exploitation Status
- unknown
- Exploit Availability
- unknown
- Patch Status
- available