Heap-based buffer overflow in Microsoft Windows and Windows Server - CVE-2026-97810

Vulnerability details

The vulnerability allows a local user to escalate privileges to SYSTEM.

The vulnerability exists due to a heap-based buffer overflow in Windows Container Isolation FS Filter Driver (unionfs.sys) when the driver is exploited locally. A local user can exploit the buffer overflow to escalate privileges to SYSTEM.

Successful exploitation requires a deep understanding of the system and depends on factors that may include the environment, system configuration, and additional security measures.

Affected software

How to mitigate CVE-2026-97810

External References

• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2026-97810
• https://support.microsoft.com/help/5127648

Related Security Bulletins

• Multiple vulnerabilities in Microsoft Windows