#microsoft-defender
16 stories taggedmicrosoft-defender.
Microsoft's Own Antivirus Driver Can Be Turned Into a Weapon at Boot
Check Point researchers show how BTR.sys, the trusted cleanup tool inside Microsoft Defender, can be steered to wipe files and registry keys before Windows even finishes starting.
Microsoft Pushes 22 Security Fixes, Six Rated Maximum Severity
A batch of patches covers Microsoft's cloud and identity products, with six flaws scoring a perfect 10 out of 10 on the severity scale. Most fixes apply automatically, but one Defender vulnerability is still waiting for a patch.
Windows Defender Crashed Mid-Scan After Buggy Update, Microsoft Ships Fix
A faulty signature update knocked out Microsoft's built-in antivirus on Windows 10 and 11 machines this week, leaving scans failing and some users reinstalling their operating system before a patch arrived.
Microsoft Ties 30+ Rotating Domains to MacSync, a New Mac Data-Stealing Malware
Defender Experts traced the macOS stealer across shifting web infrastructure by matching endpoint and network behaviour, not just domain names.
Akira gang reboots into Safe Mode to blind security tools, then fumbles the ransom
The hackers walked in through a SonicWall VPN with no second login step, but their own ransomware ran out of memory before it could lock a single file.
Researcher publishes 'ShieldBreak' code that claims to defeat a recent Microsoft Defender fix
A proof-of-concept from a researcher known as Chaotic Eclipse says the patch for CVE-2026-50656 can still be bypassed to gain full control of Windows machines.
Microsoft Warns of Two ACR Stealer Campaigns Stealing Credentials Through Fake Fixes
Between late April and mid-June 2026, two separate criminal campaigns used a trick called ClickFix to persuade workers to hand over browser passwords, session tokens, and business documents, with no software flaw required.
Microsoft Patches 'RoguePlanet' Defender Flaw a Month After Public Disclosure
The privilege escalation bug in the Malware Protection Engine sat exposed for weeks before Redmond shipped a fix.
Microsoft patches 'RoguePlanet' Defender flaw after researcher publishes exploit in disclosure spat
The zero-day let attackers hand themselves the keys to a fully patched Windows machine. It was revealed by a researcher publicly feuding with Microsoft.
Windows Clipper Worm Phones Home Over Tor, Swaps Crypto Wallets via ActiveX
Microsoft says the campaign, active since February, uses USB-borne LNK files and Windows Script Host to drop a bundled Tor proxy that talks to a .onion C2.
Microsoft Acknowledges 'RoguePlanet' Defender Zero-Day, Patch Still in the Works
CVE-2026-50656 is a privilege escalation bug in the Malware Protection Engine — the component sitting at the heart of every Defender install.
RoguePlanet Zero-Day Drops as Nightmare Eclipse–Microsoft Feud Reaches New Low
A race-condition bug in Microsoft Defender can yield a SYSTEM shell on fully patched Windows 11 and 10. No patch exists. The researcher dropped it the day after June Patch Tuesday.
RoguePlanet PoC Drops: Another Defender Race Condition, Another Path to SYSTEM
An anonymous researcher publishing as Chaotic Eclipse dropped a proof-of-concept against Microsoft Defender that wins SYSTEM on fully patched Windows — when the race goes their way.
Microsoft Rushes Fixes for Two Actively Exploited Defender Zero-Days as CISA Adds Both to KEV
A disgruntled researcher's GitHub exploits may be behind attacks on the Malware Protection Engine and Antimalware Platform — but Microsoft isn't saying so.
Two Defender flaws under active exploitation, Microsoft confirms
A SYSTEM-level link-following bug and a denial-of-service issue in Microsoft Defender are both being abused in the wild.