Emergency Fix for Windows Anti-Malware Flaw Leads May’s Patch Tuesday
Summary: Microsoft released an out-of-band emergency update on May 8, 2017, ahead of its regular Patch Tuesday, to fix a flaw in its Malware Protection Engine present in most of its anti-malware offerings, including Forefront, Security Essentials and Windows Defender. Google researchers Natalie Silvanovich and Tavis Ormandy reported the flaw, which Microsoft said could be triggered when a specially crafted file is scanned, with real-time protection causing automatic scanning and exploitation.
Why it matters: The bug sat inside the anti-malware software itself, so a crafted file could run malware the moment it was scanned rather than being caught by the scanner - the protection layer became the attack path for any organization running these products with real-time protection on.
Read the original at Krebs on Security ↗
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