Out-of-bounds write in Microsoft Windows and Windows Server - CVE-2026-96219
Published: October 14, 2026
Vulnerability identifier: #VU155423
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-2026-96219
CWE-ID: CWE-787
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to execute code on the target system.
The vulnerability exists due to an out-of-bounds write in Windows Local Security Authority Subsystem Service (LSASS) when processing network packets. A remote attacker can send a specially crafted packet to an affected service over the network to execute code on the target system.
No user interaction is required.
Affected software
Microsoft Windows
Windows Server
Windows Server
How to mitigate CVE-2026-96219
Install security update from vendor's website.
Microsoft Windows - addressed in versions 10 21H2 10.0.19044.7807, 10 1809 10.0.17763.9376, 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 2019 10.0.17763.9376, 2022 10.0.20348.5761, 2025 10.0.26100.33650
Windows Server - addressed in versions 2019 10.0.17763.9376, 2022 10.0.20348.5761, 2025 10.0.26100.33650