Vulnerability · Published Sep 9, 2025 · Assigned by microsoft
CVE-2025-53809Windows Local Security Authority Subsystem Service (LSASS) Denial of Service Vulnerability
Medium 6.5
In plain English
A medium-severity improper input validation in Windows 11 Version 24H2 from Microsoft. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 1.6% (higher than 76% of all known vulnerabilities).
Severity (CVSS 3.1)6.5Medium
Exploit odds (30 days)1.6%top 24.5% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
Improper input validation in Windows Local Security Authority Subsystem Service (LSASS) allows an authorized attacker to deny service over a network.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Microsoft | Windows 11 Version 24H2 | 10.0.26100.0 – before 10.0.26100.6584 |
| Microsoft | Windows Server 2025 | 10.0.26100.0 – before 10.0.26100.6584 |
| Microsoft | Windows Server 2025 (Server Core installation) | 10.0.26100.0 – before 10.0.26100.6584 |
Weakness: CWE-20 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C
References
- Windows Local Security Authority Subsystem Service (LSASS) Denial of Service Vulnerability vendor-advisory, patch