Description
Improper verification of cryptographic signature in Windows Schannel allows an unauthorized attacker to perform spoofing over a network.
Affected products
microsoft: windows 11 23h2; microsoft: windows 11 24h2; microsoft: windows 11 25h2; microsoft: windows 11 26h1; microsoft: windows 11 26h2; microsoft: windows server 2022; microsoft: windows server 2025
References1
- msrc.microsoft.com/update-guide/vulnerability/CVE-2026-85818 Vendor AdvisoryPatch
Metrics
- CVSS 3.1
-
9.0
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 36 · as of 11 November 2026
- CWE
- CWE-347
Could this be exploited in your environment?
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