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.

CISA says ransomware gangs are exploiting Microsoft Defender’s BlueHammer flaw, patched in April 2026 after zero-day reports.

BlueHammer became public on April 2 in an unusual fashion. A researcher using the names Chaotic Eclipse and Nightmare Eclipse ...

Windows Defender "BlueHammer" vulnerability now exploited as part of malware campaigns — event demonstrates lack of security ...

Arctic Wolf says Anubis affiliates abused RMM tools, VPN logins, RDP, PsExec, and cloud-transfer tools before ransomware ...

Official support for Windows 10 has ended, and its security certificates are expiring. Your system is at risk, and Microsoft ...

Do you still need third-party antivirus on your Windows PC?

Researchers identified what they believe is the first documented case of a ransomware operation, JadePuffer, conducted ...

Attackers impersonate Interpol to trick small businesses into downloading ransomware hidden in password-protected archives.

ThreatsDay Bulletin covers this week’s cyber threats, from phishing and ransomware to exposed AI systems, sandbox flaws, and ...

This month’s updates help security and IT teams strengthen identity and multicloud foundations, protect data wherever it ...

When the IBM PC was new, I served as the president of the San Francisco PC User Group for three years. That’s how I met PCMag’s editorial team, who brought me on board in 1986. In the years since that ...