Use-after-free in Microsoft Windows and Windows Server - CVE-2026-100219
Published: October 13, 2026
Vulnerability identifier: #VU154241
CSH Severity: High
CVSS v4: 9.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-100219
CWE-ID: CWE-416
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to execute arbitrary code.
The vulnerability exists due to use-after-free in Microsoft QUIC when processing network packets. A remote attacker can send a specially crafted packet to an affected service over the network to execute arbitrary code.
No user interaction is required.
Affected software
Microsoft Windows
Windows Server
Windows Server
How to mitigate CVE-2026-100219
Install security update from vendor's website.
Microsoft Windows - addressed in versions 11 23H2 10.0.22631.7652, 11 24H2 10.0.26100.9711, 11 25H2 10.0.26200.9711, 11 26H1 10.0.28000.3231
Windows Server - addressed in versions 2022 10.0.20348.5761, 2025 10.0.26100.33650
Windows Server - addressed in versions 2022 10.0.20348.5761, 2025 10.0.26100.33650