Vulnerability · Published Jul 14, 2026 · Assigned by microsoft

CVE-2026-54990Remote Desktop Client Remote Code Execution Vulnerability

Critical 9.8

In plain English

A critical-severity heap buffer overflow in Windows 11 Version 24H2 from Microsoft. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.8% (higher than 57% of all known vulnerabilities).

Severity (CVSS 3.1)9.8Critical
Exploit odds (30 days)0.8%top 42.6% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

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

Affected products (as reported)

VendorProductVersions
Microsoft Windows 11 Version 24H2 10.0.26100.0 – before 10.0.26100.8875
Microsoft Windows 11 Version 25H2 10.0.26200.0 – before 10.0.26200.8875
Microsoft Windows 11 version 26H1 10.0.28000.0 – before 10.0.28000.2525
Microsoft Windows Server 2025 10.0.26100.0 – before 10.0.26100.33158
Microsoft Windows Server 2025 (Server Core installation) 10.0.26100.0 – before 10.0.26100.33158

Weakness: CWE-122 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C

References