CVE-2026-85818 CRITICAL

CVE-2026-85818: Windows Schannel Spoofing Vulnerability

Vendor Microsoft
Product Windows 11 version 23H2
Weakness CWE-347
Published October 13, 2026
Last update October 26, 2026
View on NVD All CVEs

CVSS base score

9.0/10
Attack vector Network
Attack complexity High
Privileges required None
User interaction None
Confidentiality High
Integrity High

CVSS vector

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H/E:U/RL:O/RC:C

What the vulnerability does

01Description

Improper verification of cryptographic signature in Windows Schannel allows an unauthorized attacker to perform spoofing over a network.

Key dates

02Disclosure timeline

October 13, 2026 CVE published
October 26, 2026 Record updated

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