Windows Defender
New Windows Defender zero-day blocks Microsoft antivirus updates
Over the weekend, security researcher Abdelhamid Naceri (also known as Nightmare Eclipse) released another Microsoft Defender zero-day exploit that blocks antivirus updates. Naceri named it BigDiskBuster and said it is similar to another Defender zero-day known as UnDefend, which he released in April and that allowed standard users to block definition updates. The security researcher added […]
Microsoft fixes known issue causing Windows Defender crashes
Microsoft has resolved a bug that caused Windows Defender to crash after a recent security update, resulting in 0xc0000005 access violation errors on some affected systems. Microsoft Defender is a security software designed to provide real-time protection against malware, viruses, ransomware, and spyware on Windows, macOS, Linux, Android, and iOS devices. According to reports on social media and Microsoft’s support site, users […]
CISA orders feds to patch BlueHammer flaw exploited as zero-day
CISA has given U.S. government agencies two weeks to secure their Windows systems against a Microsoft Defender privilege escalation vulnerability that has been exploited in zero-day attacks. Tracked as CVE-2026-33825, this high-severity security flaw allows low-privileged local threat actors to gain SYSTEM permissions on unpatched devices by exploiting an insufficient granularity of access control weakness. Microsoft patched […]