Microsoft Defender Privilege Escalation Vulnerability WID-SEC-2026-1155

CERT-Bund published advisory WID-SEC-2026-1155 identifying a local privilege escalation vulnerability in Microsoft Defender. The flaw allows an authenticated local attacker to escalate privileges by exploiting the security software itself. With no remote attack vector and a CVSS score of 7.8, organizations running Windows systems with Microsoft Defender should monitor for vendor patches.

Affected parties running Windows environments with Microsoft Defender should prioritize applying vendor-released patches once available and implement compensating controls such as limiting local user privileges until the vulnerability is remediated. Security teams should track the CVE reference and monitor CERT-Bund and Microsoft channels for updated mitigation guidance.