CVE-2025-53809 | Windows Local Security Authority Subsystem Service (LSASS) Denial of Service Vulnerability

Improper input validation in Windows Local Security Authority Subsystem Service (LSASS) allows an authorized attacker to deny service over a network.

Published: 2025-09-09 Last update: 2025-09-22 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2025-53809 is rated Moderate Risk (50.1/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 0.56%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2025-53809

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-26 0.48% 0.56% +0.08%
2 2026-05-15 0.36% 0.48% +0.12%
3 2026-05-05 — 0.36% —

Full EPSS history (8 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-53809

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.5 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 2.8 3.6 [email protected]

Weakness enumeration for CVE-2025-53809

Affected software / configurations for CVE-2025-53809

Vendor Product Version Raw CPE
microsoft windows_11_24h2 < 10.0.26100.6508 cpe:2.3:o:microsoft:windows_11_24h2:*:*:*:*:*:*:*:*
microsoft windows_server_2025 < 10.0.26100.6508 cpe:2.3:o:microsoft:windows_server_2025:*:*:*:*:*:*:*:*

References for CVE-2025-53809

cvelogic Threat Intelligence