Undefend

vulnerabilities 2026-04-18
RedSun and UnDefend: Two More Defender Zero-Days Dropped, All Three Now Exploited in the Wild
The same disgruntled researcher who dropped BlueHammer has now released RedSun and UnDefend. Huntress confirms all three Windows Defender zero-days are now being weaponized in hands-on-keyboard intrusions. Two remain unpatched.
windows zero-day privilege-escalation windows-defender redsun undefend bluehammer huntress

RedSun and UnDefend: Two More Defender Zero-Days Dropped, All Three Now Exploited in the Wild