CVE-2026-83516

Windows Local Security Authority Subsystem Service (LSASS) Denial of Service Vulnerability

CVE-2026-83516 is fixed in 16 products on 1 platform, first by KB5126651, released October 13, 2026. It is not reported as exploited. Patch Radar priority: High.

High
CVSS
7.5
Important
Exploitation
None reported
Exploitation Unlikely
CISA KEV
Not listed
Not in the Known Exploited Vulnerabilities catalog
EPSS
0.0133
71st percentile

<p>Out-of-bounds read in Windows Local Security Authority Subsystem Service (LSASS) allows an unauthorized attacker to deny service over a network.</p>

Where it's fixed

ProductFixed inFixReleased
Microsoft
Windows 10 Version 1809 for 32-bit Systems 17763.9376 KB5126651 Oct 13, 2026
Windows 10 Version 1809 for x64-based Systems 17763.9376 KB5126651 Oct 13, 2026
Windows 11 Version 24H2 for ARM64-based Systems KB5127648 Oct 13, 2026
Windows 11 Version 24H2 for x64-based Systems KB5127648 Oct 13, 2026
Windows 11 Version 25H2 for ARM64-based Systems KB5127648 Oct 13, 2026
Windows 11 Version 25H2 for x64-based Systems KB5127648 Oct 13, 2026
Windows 11 Version 26H1 for ARM64-based Systems 28000.3231 KB5127646 Oct 13, 2026
Windows 11 Version 26H2 for ARM64-based Systems KB5127648 Oct 13, 2026
Windows 11 Version 26H2 for x64-based Systems KB5127648 Oct 13, 2026
Windows 11 version 26H1 for x64-based Systems 28000.3231 KB5127646 Oct 13, 2026
Windows Server 2019 17763.9376 KB5126651 Oct 13, 2026
Windows Server 2019 (Server Core installation) 17763.9376 KB5126651 Oct 13, 2026
Windows Server 2022 20348.5761 KB5126655 Oct 13, 2026
Windows Server 2022 (Server Core installation) 20348.5761 KB5126655 Oct 13, 2026
Windows Server 2025 26100.33650 KB5126646 Oct 13, 2026
Windows Server 2025 (Server Core installation) 26100.33650 KB5126646 Oct 13, 2026

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