Review reviewHigh

CVE-2026-20854

Microsoft Windows 11 Version 24H2, Windows 11 Version 25H2, Windows Server 2025

Use after free in Windows Local Security Authority Subsystem Service (LSASS) allows an authorized attacker to execute code over a network.

PRIORITY ASSESSMENT

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV

Exploit probability-

Technical severityCVSS 7.5

Use after free in Windows Local Security Authority Subsystem Service (LSASS) allows an authorized attacker to execute code over a network.

Product: Microsoft Windows 11 Version 24H2, Windows 11 Version 25H2, Windows Server 2025
Affected versions: >= 10.0.26100.0 < 10.0.26100.7623, >= 10.0.26200.0 < 10.0.26200.7623, >= 10.0.26100.0 < 10.0.26100.32230, < 10.0.26100.7623, < 10.0.26200.7623, < 10.0.26100.32230
Fixed versions: 10.0.26100.7623, 10.0.26200.7623, 10.0.26100.32230

Confirm exposure before applying a vendor-supported change.

1
Identify
Confirm that Microsoft Windows 11 Version 24H2, Windows 11 Version 25H2, Windows Server 2025 and an affected version are present.
2
Prioritize
Combine exploitation signals with asset exposure and business criticality.
3
Remediate
Follow the vendor advisory or supported update path and preserve rollback options.
4
Verify
Recheck the version, service health, access paths, and relevant logs.