Description
Improper input validation in Windows Local Security Authority Subsystem Service (LSASS) allows an authorized attacker to deny service over a network.
Affected products
microsoft: windows 11 24h2; microsoft: windows server 2025
References1
- msrc.microsoft.com/update-guide/vulnerability/CVE-2025-53809 Vendor Advisory
Metrics
- CVSS 3.1
-
6.5
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 2% percentile: 76 · as of 8 November 2026
- CWE
- CWE-20
Could this be exploited in your environment?
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