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CVE-2025-53809 (GCVE-0-2025-53809)

Vulnerability from cvelistv5 – Published: 2025-09-09 17:01 – Updated: 2026-02-20 16:00
VLAI
Title
Windows Local Security Authority Subsystem Service (LSASS) Denial of Service Vulnerability
Summary
Improper input validation in Windows Local Security Authority Subsystem Service (LSASS) allows an authorized attacker to deny service over a network.
Severity
6.5 (Medium)
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
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-09-09 18:00 UTC
CWE
  • CWE-20 - Improper Input Validation
Assigner
References
Impacted products
Vendor Product Version CPE status
Microsoft Windows 11 Version 24H2 Affected: 10.0.26100.0 , < 10.0.26100.6584 (custom)
guessed Create a notification for this product.
Microsoft Windows Server 2025 Affected: 10.0.26100.0 , < 10.0.26100.6584 (custom)
guessed Create a notification for this product.
Microsoft Windows Server 2025 (Server Core installation) Affected: 10.0.26100.0 , < 10.0.26100.6584 (custom)
guessed Create a notification for this product.
Date Public
2025-09-09 07:00
Show details on NVD website
To clipboard 

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Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.