Review reviewHigh

CVE-2026-54990

Microsoft Windows 11 Version 24H2, Windows 11 Version 25H2, Windows 11 version 26H1

Heap-based buffer overflow in Remote Desktop Client allows an unauthorized 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 probability0.55%

Technical severityCVSS 8.8

Heap-based buffer overflow in Remote Desktop Client allows an unauthorized attacker to execute code over a network.

Product: Microsoft Windows 11 Version 24H2, Windows 11 Version 25H2, Windows 11 version 26H1
Affected versions: >= 10.0.26100.0 < 10.0.26100.8875, >= 10.0.26200.0 < 10.0.26200.8875, >= 10.0.28000.0 < 10.0.28000.2525, >= 10.0.26100.0 < 10.0.26100.33158, < 10.0.26100.8875, < 10.0.26200.8875, < 10.0.28000.2269, < 10.0.28000.2525, < 10.0.26100.33158
Fixed versions: 10.0.26100.8875, 10.0.26200.8875, 10.0.28000.2269, 10.0.28000.2525, 10.0.26100.33158

Confirm exposure before applying a vendor-supported change.

1
Identify
Confirm that Microsoft Windows 11 Version 24H2, Windows 11 Version 25H2, Windows 11 version 26H1 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.