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Microsoft emergency update: Malware Engine needs, erm, malware protection
Stop appreciating the irony and go install the patch now
Microsoft has posted an out-of-band security update to address a remote code execution flaw in its Malware Protection Engine.
Redmond says the flaw, dubbed CVE-2017-11937, has not yet been exploited in the wild. Because it is an out-of-band critical fix, however, it should be installed as soon as possible. For most users, this will happen automatically.
The security hole is present in Windows Defender and Microsoft Security Essentials, as well as Endpoint Protection, Forefront Endpoint Protection, and Exchange Server 2013 and 2016.