EUVD-2026-21070
GHSA-f5h9-5q52-qrx7
Severity by source
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:L/SC:H/SI:L/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:Red
Primary rating from NVD.
CVSS VectorNVD
Lifecycle Timeline
5DescriptionCVE.org
Missing hash/digest size and OID checks allow digests smaller than allowed when verifying ECDSA certificates, or smaller than is appropriate for the relevant key type, to be accepted by signature verification functions. This could lead to reduced security of ECDSA certificate-based authentication if the public CA key used is also known. This affects ECDSA/ECC verification when EdDSA or ML-DSA is also enabled.
AnalysisAI
ECDSA signature verification in wolfSSL 3.12.0 through 5.9.0 accepts cryptographically weak digest sizes below protocol-mandated minimums, enabling authentication bypass when attackers possess the public CA key. Authenticated network attackers can exploit this to compromise confidentiality and integrity of certificate-based sessions. Vulnerability arises specifically when EdDSA or ML-DSA algorithms are concurrently enabled alongside ECDSA/ECC verification. No public exploit identified at time of analysis.
Technical ContextAI
Root cause: missing validation of hash digest size and OID parameters against ECDSA key type requirements (CWE-295). Signature verification functions fail to enforce minimum digest lengths per FIPS 186-4/RFC 5753, accepting truncated hashes that reduce effective security strength below 112-bit equivalent. Conditional trigger requires EdDSA or ML-DSA cryptographic modules loaded concurrently with ECDSA verification routines.
RemediationAI
Vendor-released patch: upgrade to wolfSSL version 5.9.1 or later, which enforces strict digest size validation aligned with ECDSA key parameters and NIST SP 800-57 guidance. Organizations unable to upgrade immediately should disable EdDSA and ML-DSA algorithm support if not operationally required, reducing attack surface per vendor advisory. Review ECDSA certificate chains for anomalous digest sizes in production PKI infrastructure. Implement network segmentation to restrict privileged user access to certificate validation endpoints. Official fix details: https://github.com/wolfSSL/wolfssl/pull/10131. Confirm version compliance through wolfSSL_lib_version() API call post-deployment.
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Same weakness CWE-295 – Improper Certificate Validation
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