CVE-2026-6329: PKCS#12 MAC verification uses an attacker-controlled comparison length, weakening the integrity check on the MAC and allowing a mismatched MAC to be accepted. The PKCS#12 verify pa

mediumCVSS 6.5CVE-2026-6329

PKCS#12 MAC verification uses an attacker-controlled comparison length, weakening the integrity check on the MAC and allowing a mismatched MAC to be accepted. The PKCS#12 verify path compared the locally computed HMAC against the MAC parsed from the PKCS#12 structure using a length taken directly from the attacker-supplied input, without first verifying that it equals the length of the digest actually produced by the configured algorithm. A truncated or zero-length stored MAC could therefore be accepted, defeating the integrity protection of the MAC.

Details

Source: NVD Recent CVEs (US · database · site)
Severity: medium — CVSS 6.5
Published: 2026-06-25
Last updated: 2026-06-27
Exploitation: Not in CISA KEV at last sync

Original advisory: https://nvd.nist.gov/vuln/detail/CVE-2026-6329

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Low exploitation riskCVE-2026-63290.16% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 6% of all scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-6329	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

mediumCVE-2026-6329: PKCS#12 MAC verification uses attacker-controlled comparison lengthmsrc

Recent advisories for PKCS#12 MAC verification

A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.

mediumCVE-2026-6329: PKCS#12 MAC verification uses attacker-controlled comparison lengthmsrc · 2026-06-09