Known exploited · Microsoft
CVE-2017-8540: Microsoft Malware Protection Engine Improper Restriction of Operations Vulnerability
What it is
The Microsoft Malware Protection Engine running on Microsoft Forefront and Microsoft Defender on Microsoft Windows Server 2008 SP2 and R2 SP1, Windows 7 SP1, Windows 8.1, Windows Server 2012 Gold and R2, Windows RT 8.1, Windows 10 Gold, 1511, 1607, and 1703, and Windows Server 2016, Microsoft Exchange Server 2013 and 2016, does not properly scan a specially crafted file leading to memory corruption. aka "Microsoft Malware Protection Engine Remote Code Execution Vulnerability".
- Vendor
- Microsoft
- Product
- Malware Protection Engine
- Added to KEV
- March 3, 2022
- CISA due date
- March 24, 2022
- Ransomware use
- Unknown
What CISA requires
Apply updates per vendor instructions.
Forensic triage
No
What to do now
- Find every instance of Malware Protection Engine you run, including the forgotten ones, and check its version against the vendor advisory.
- Apply the vendor's fix or mitigation, before March 24, 2022 if you are bound by CISA's deadline, sooner if it faces the internet.
- Assume it was tried against you already: look for signs of exploitation from the date it was added, not from the day you patched.
References
H2 Security
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Start freeSource: CISA Known Exploited Vulnerabilities Catalog (public domain), catalog version 2026.10.01.