CISA KEV catalog
Confirmed active exploitation.
Listed in CISA's catalog of Known Exploited Vulnerabilities: attackers are using it in real attacks. Patch it with priority.
- Name
- Microsoft Malware Protection Engine Improper Restriction of Operations Vulnerability
- Added to catalog
- Remediation due date (US federal)
- Required action
- Apply updates per vendor instructions.
Description
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", a different vulnerability than CVE-2017-8538 and CVE-2017-8541.
Affected products
microsoft: malware protection engine; microsoft: windows 10 1507; microsoft: windows 10 1511; microsoft: windows 10 1607; microsoft: windows 10 1703; microsoft: windows 7; microsoft: windows 8.1; microsoft: windows rt 8.1; microsoft: windows server 2008; microsoft: windows server 2012; microsoft: windows server 2016; microsoft: endpoint protection; microsoft: exchange server; microsoft: forefront endpoint protection; microsoft: forefront security
References9
- portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-… MitigationPatchVendor Advisory
- portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-… MitigationPatchVendor Advisory
- www.exploit-db.com/exploits/42088/ ExploitThird Party AdvisoryVDB Entry
- www.exploit-db.com/exploits/42088/ ExploitThird Party AdvisoryVDB Entry
- www.securityfocus.com/bid/98703 Broken LinkThird Party AdvisoryVDB Entry
- www.securitytracker.com/id/1038571 Broken LinkThird Party AdvisoryVDB Entry
- www.securityfocus.com/bid/98703 Broken LinkThird Party AdvisoryVDB Entry
- www.securitytracker.com/id/1038571 Broken LinkThird Party AdvisoryVDB Entry
- www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=… US Government Resource
Metrics
- CVSS 3.1
-
7.8
HIGH
Score source: NVD
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 72% percentile: 99 · as of 8 November 2026
- CWE
- CWE-787
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