- Critical 9.0
CVE-2026-85818
Improper verification of cryptographic signature in Windows Schannel allows an unauthorized attacker to perform spoofing over a network.
Scores
The facts
- Published
- 13 October 2026
- Last changed
- 16 October 2026
- NVD status
- Analyzed
- Severity
- Critical, CVSS 9.0 out of 10 (version 3.1)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H - Weakness
- Affects
- microsoft windows 11 23h2
- microsoft windows 11 24h2
- microsoft windows 11 25h2
- microsoft windows 11 26h1
- microsoft windows 11 26h2
- Known exploited
- Not in the CISA Known Exploited Vulnerabilities catalogue in this build.
- EPSS
- 0.4% chance of exploitation activity in the next 30 days (percentile 34).
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