SB2026051324 - Multiple vulnerabilities in Microsoft Windows Kernel

Description

This security bulletin contains information about 3 vulnerabilities.

1) Untrusted Pointer Dereference (CVE-ID: CVE-2026-40369)

CWE-ID: CWE-822 - Untrusted Pointer Dereference

CVSSv4: 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/E:P/U:Clear

The vulnerability allows a local user to escalate privileges the target system.

The vulnerability exists due to untrusted pointer dereference in Windows Kernel. A local user can gain elevated privileges on the system.

2) Heap-based buffer overflow (CVE-ID: CVE-2026-35420)

CWE-ID: CWE-122 - Heap-based Buffer Overflow

CVSSv4: 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/E:U/U:Clear

The vulnerability allows a local user to escalate privileges on the target system.

The vulnerability exists due to a boundary error in Windows Kernel. A local user can pass specially crafted data to the application, trigger a heap-based buffer overflow and gain elevated privileges on the system.

3) Heap-based buffer overflow (CVE-ID: CVE-2026-33841)

CWE-ID: CWE-122 - Heap-based Buffer Overflow

CVSSv4: 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/E:U/U:Clear

The vulnerability allows a local user to escalate privileges on the target system.

The vulnerability exists due to a boundary error in Windows Kernel. A local user can pass specially crafted data to the application, trigger a heap-based buffer overflow and gain elevated privileges on the system.

Remediation

Install update from vendor's website.

References

• https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-40369
• https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-35420
• https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-33841