CVE-2026-33825

Overview Attribute Value CVE ID CVE-2026-33825 CVSS Score 7.8 Vendor Microsoft Product Windows Defender Antivirus (Windows 10/11, Server 2016+) Vulnerability Type TOCTOU + Path Confusion → Local Privilege Escalation Status ✅ Patched (April 14, 2026 Patch Tuesday) CWE CWE-367 (Time-of-check Time-of-use Race Condition) KEV Added Not yet Exploitation Status ⚠️ PoC public, no confirmed in-the-wild attacks yet Patch Status ❌ Unpatched (as of April 12, 2026) Affected Versions Version Status Windows 10 (1709+) ❌ Vulnerable Windows 11 ❌ Vulnerable Windows Server 2016+ ⚠️ Partial (elevated admin, not full SYSTEM) Windows 10 (pre-1709) ✅ Not affected (no Cloud Files API) Description BlueHammer is a local privilege escalation vulnerability in Microsoft Defender Antivirus that chains a TOCTOU race condition with path confusion in Defender’s signature update workflow. A standard user can exploit Defender’s own privileged update mechanism to leak the SAM hive, decrypt credentials, and achieve SYSTEM privileges. ...