CISA has ordered U.S. federal agencies to patch a Microsoft Defender privilege escalation flaw (dubbed BlueHammer) that has been exploited in zero-day attacks.

GreenPlasma Windows CTFMON Arbitrary Section Creation Elevation of Privileges Vulnerability - Nightmare-Eclipse/GreenPlasma

CISA confirmed on Monday that ransomware gangs are now exploiting a Microsoft Defender privilege escalation vulnerability, dubbed BlueHammer, that has previously been abused in zero-day attacks.

Exploit code has been released for an unpatched Windows privilege escalation flaw reported privately to Microsoft, allowing attackers to gain SYSTEM or elevated administrator permissions.

CISA confirmed on Monday that ransomware gangs are now exploiting a Microsoft Defender privilege escalation vulnerability, dubbed BlueHammer, that has previously been abused in zero-day attacks. [...]

A zero-day BlueHammer Windows exploit was leaked due to alleged Microsoft Security Response Center ineptitude. Although it's since been patched, it was live for two weeks, suggesting that Microsoft's ...

Howler Cell outlines the BlueHammer exploit, a Windows zero-day leveraging Defender's update process to escalate privileges, remaining unpatched.

Exploit code has been released for an unpatched Windows privilege escalation flaw reported privately to Microsoft, allowing attackers to gain SYSTEM or elevated administrator permissions.

Attackers exploit three Microsoft Defender zero-days, code-named BlueHammer, RedSun, and UnDefend, to gain elevated access.

Die Zero-Day-Lücken im Windows Defender mit den Namen BlueHammer, RedSun und UnDefend werden offenbar attackiert.

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Why the BlueHammer Windows Exploit Matters More Than Most People Think

A Microsoft Defender vulnerability tracked as BlueHammer and CVE-2026-33825 is being exploited in ransomware attacks

A Windows zero-day called BlueHammer exploits Defender's own update process to give attackers full SYSTEM access. The exploit code is public and unpatched.

A buggy but functional proof-of-concept (PoC) exploit for an unpatched Windows local privilege escalation vulnerability dubbed BlueHammer has been published on GitHub by someone who goes by the handle Chaotic Eclipse and Nightmare Eclipse. Several security researchers have fixed the bugs in the exploit and made it work on patched Windows 10, 11, and Windows Server systems, and the question now is whether Microsoft is planning or working on a fix. The BlueHammer PoC exploit …