Out-of-bounds read in Microsoft Windows and Windows Server - CVE-2026-83856

Vulnerability details

The vulnerability allows a remote attacker to execute arbitrary code.

The vulnerability exists due to an out-of-bounds read in Windows Event Logging Service when handling network communications. A remote attacker can exploit the service over a network to execute arbitrary code.

User interaction is required. Successful exploitation requires a deep understanding of the system and depends on factors such as the environment, system configuration, and additional security measures.

Affected software

How to mitigate CVE-2026-83856

External References

• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2026-83856
• https://support.microsoft.com/help/5126655

Related Security Bulletins

• Multiple vulnerabilities in Microsoft Windows