CVE-2025-53809 json
Windows Local Security Authority Subsystem Service (LSASS) Denial of Service Vulnerability
published 2025-09-09 13 mo ago modified 2026-10-18 21 d ago also EUVD-2025-27321
- cvss
- 6.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.6%
- EPSS 1.6% chance of exploitation in 30 days, percentile 75%
- public exploits
- 0
- none known
Summary
Improper input validation in Windows Local Security Authority Subsystem Service (LSASS) allows an authorized attacker to deny service over a network.
Patch / fix
- Microsoft Windows 11 Version 24H2 10.0.26100.6584
- Microsoft Windows Server 2025 10.0.26100.6584
- Microsoft Windows Server 2025 (Server Core installation) 10.0.26100.6584
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 13 mo ago
Exploit prediction
1.57% chance of exploitation in the next 30 days, higher than 75% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 6.5 | 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 |
| CNA | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
Affected products
- Microsoft Windows 11 Version 24H2
- Microsoft Windows Server 2025
- Microsoft Windows Server 2025 (Server Core installation)
Classification
- Weakness
-
- CWE-20 Improper Input Validation
References
-
msrc.microsoft.com
/update-guide/vulnerability/CVE-2025-53809
vendor-advisory, patch
Sources
- CVE List CVE-2025-53809
- NVD CVE-2025-53809
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.