Integer underflow in Microsoft Windows and Windows Server - CVE-2026-50300

 

Integer underflow in Microsoft Windows and Windows Server - CVE-2026-50300

Published: July 17, 2026


Vulnerability identifier: #VU137992
CSH Severity: Low
CVSS v4: 4.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-50300
CWE-ID: CWE-191
Exploitation vector: Local access
Exploit availability: No public exploit available

Vulnerability details

The vulnerability allows a local user to disclose sensitive information.

The vulnerability exists due to integer underflow in Windows Kernel when handling crafted local operations. A local user can trigger the integer underflow to disclose sensitive information.

An attacker who successfully exploits this vulnerability could read small portions of heap memory.


Affected software

Microsoft Windows
Windows Server

How to mitigate CVE-2026-50300

Install security update from vendor's website.

Microsoft Windows - addressed in versions 10 21H2 10.0.19044.7548, 10 22H2 10.0.19045.7548, 10 1607 10.0.14393.9339, 10 1809 10.0.17763.9020, 11 24H2 10.0.26100.8875, 11 25H2 10.0.26200.8875, 11 26H1 10.0.28000.2269, 11 26H1 10.0.28000.2525
Windows Server - addressed in versions 2012 R2 6.3.9600.23291, 2016 10.0.14393.9339, 2019 10.0.17763.9020, 2022 10.0.20348.5386, 2025 10.0.26100.33158

External References

Related Security Bulletins