A hostname verification bypass in GnuTLS v3.8.13 allows attackers to circumvent the Common Name fallback mechanism and eavesdrop on communications via a crafted certificate.

HighVendor CVSS 7.4 / 10 1 CVE Published Oct 11, 2026 at 1:53 AM UTC

Summary

Mariner

Release Notes

Oct 11, 2026 at 1:53 AM UTC
Published by Microsoft Security Response Center
The publication date reported by the vendor.
Oct 12, 2026 at 3:36 PM UTC
Updated by Microsoft Security Response Center
The vendor changed the advisory after it was first published.
Oct 13, 2026 at 10:45 AM UTC
Added to SecurityAlert
We collected the advisory from the official source.
Oct 21, 2026 at 1:15 AM UTC
Confirmed at the source
Our collector saw this advisory during a later source check.

Details collected from Microsoft Security Response Center.

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