Description

HMAC zero-length tag forgery in EVP_DigestVerifyFinal, where a zero-length tag could be accepted as valid during HMAC verification. In the OpenSSL-compatibility HMAC verify path the supplied signature length was only checked as not exceeding the MAC length, so a zero-length or otherwise truncated tag could pass verification. The fix requires the supplied tag length to exactly equal the MAC length and rejects a zero-length MAC, so a forged short or empty tag is no longer accepted.

Severity (CVSS)

Base score2.1
SeverityLow
VersionCVSS 4.0
VectorCVSS:4.0/AV:L/AC:H/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
Provided byCNA

Weaknesses

  • CWE-347 — CWE-347 Improper Verification of Cryptographic Signature

Affected products

VendorProductVersions
wolfSSLwolfSSL3.15.5 to <=5.9.1

References

Authoritative sources

This page is a snapshot. For the latest enrichment and updates, view the record on CVE.org or the NVD.

Generated from the official CVE List on 26 Jun 2026 07:05 UTC.