Double free in Microsoft Windows and Windows Server - CVE-2026-20832
Published: January 13, 2026
Vulnerability identifier: #VU121253
CSH Severity: Low
CVSS v4: 8.5 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-20832
CWE-ID: CWE-415
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to a boundary error in Windows Remote Procedure Call Interface Definition Language (IDL). A local user can pass specially crafted data to the application, trigger double free error and gain elevated privileges on the target system.
Affected software
Microsoft Windows
Windows Server
Windows Server
How to mitigate CVE-2026-20832
Install updates from vendor's website.
Microsoft Windows - addressed in versions 10 21H2 10.0.19044.6809, 10 22H2 10.0.19045.6809, 10 1607 10.0.14393.8783, 10 1809 10.0.17763.8276, 11 23H2 10.0.22631.6491, 11 24H2 10.0.26100.7623
Windows Server - addressed in versions 2016 10.0.14393.8783, 2019 10.0.17763.8276, 2022 23H2 10.0.25398.2092, 2022 10.0.20348.4648, 2025 10.0.26100.7623, 2025 10.0.26100.32230
Windows Server - addressed in versions 2016 10.0.14393.8783, 2019 10.0.17763.8276, 2022 23H2 10.0.25398.2092, 2022 10.0.20348.4648, 2025 10.0.26100.7623, 2025 10.0.26100.32230