CVE-2026-91769: TLS Hostname Verification Falls Back to CN After SAN Mismatch

Overview

Severity

Medium (CVSS 4.3)

CVSS Vector

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

Exploit Status

Not Exploited

Patch Tuesday

2026-Sep

Released

2026-09-27

Last Updated

2026-09-29

Affected Products (1)

Other

• 21709-17084

Revision History

• 2026-09-27: Information published.
• 2026-09-29: Information published.