Race condition in Microsoft Windows and Windows Server - CVE-2026-119961
Published: November 11, 2026
Vulnerability identifier: #VU165380
CSH Severity: High
CVSS v4: 9.2 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-119961
CWE-ID: CWE-362
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to execute arbitrary code on the target system.
The vulnerability exists due to improper synchronization of concurrent access to a shared resource in Windows Internet Information Services when handling network packets. A remote attacker can send a specially crafted packet to an affected service and win a race condition to execute arbitrary code on the target system.
Affected software
Microsoft Windows
Windows Server
Windows Server
How to mitigate CVE-2026-119961
Install security update from vendor's website.
Microsoft Windows - addressed in versions 10 21H2 10.0.19044.7846, 10 22H2 10.0.19045.7846, 10 1607 10.0.14393.9688, 10 1809 10.0.17763.9487, 11 23H2 10.0.22631.7711, 11 24H2 10.0.26100.9911, 11 24H2 10.0.26100.9974, 11 25H2 10.0.26200.9911, 11 25H2 10.0.26200.9974, 11 26H1 10.0.28000.3501
Windows Server - addressed in versions 2016 10.0.14393.9688, 2019 10.0.17763.9487, 2022 10.0.20348.5870, 2025 10.0.26100.33730, 2025 10.0.26100.33822
Windows Server - addressed in versions 2016 10.0.14393.9688, 2019 10.0.17763.9487, 2022 10.0.20348.5870, 2025 10.0.26100.33730, 2025 10.0.26100.33822