CVE-2026-20854

EUVD-2026-2173
Use after free in Windows Local Security Authority Subsystem Service (LSASS) allows an authorized attacker to execute code over a network.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTPrimary
7.5 HIGH
NETWORK
HIGH
LOW
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
microsoftCNA
7.5 HIGH
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
Base Score
CVSS 3.x
EPSS Score
Percentile: 18%
Affected Products (NVD)
VendorProductVersion
microsoftwindows_11_24h2
𝑥
< 10.0.26100.7623
microsoftwindows_11_25h2
𝑥
< 10.0.26200.7623
microsoftwindows_server_2025
𝑥
< 10.0.26100.32230
𝑥
= Vulnerable software versions
Windows Releases
Platform
Version
Windows 11
24H2 (arm64, x64)
KB5074109
25H2 (arm64, x64)
KB5074109
Windows Server 2025
Server Core
KB5073379
Standard
KB5073379
Common Weakness Enumeration
References
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20854