CVE-2026-6331: HMAC zero-length tag forgery in EVP_DigestVerifyFinal

Overview

Severity

High (CVSS 7.5)

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

Exploit Status

Not Exploited

Patch Tuesday

2026-Jun

Released

2026-07-01

EPSS Score

0.15% (percentile: 4.4%)

Affected Products (1)

Other

• 21516-17084

Revision History

• 2026-07-01: Information published.