CVE-2017-8540 — Microsoft Malware Protection Engine Improper Restriction of Operations Vulnerabi

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 20

01What is this vulnerability?

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…

02Affected products

Vendor	Product	Versions
Microsoft Corporation	Malware Protection Engine	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.

03Active exploitation status

Yes — actively exploited. Added to the CISA KEV catalog on 2022-03-03. Ransomware use: Unknown.

04Recommended remediation

• Patch to a fixed version listed in the vendor advisory (see references below).
• Mitigate with WAF rules, network egress filters, or feature flags where the patch is not yet available.
• Hunt historical logs for exploitation indicators — see Detection signatures below.

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Open the Sigma generator with a pre-filled prompt for this CVE to draft a starting detection in your stack of choice:

Open in Sigma generator →

07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

• Published: 2017-05-26T20:00:00.000Z
• Last modified: 2025-10-21T23:55:40.255Z
• Added to CISA KEV: 2022-03-03
• BOD 22-01 due: 2022-03-24

09References

• portal.msrc.microsoft.com — https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2017-8540
• www.securityfocus.com — http://www.securityfocus.com/bid/98703
• www.exploit-db.com — https://www.exploit-db.com/exploits/42088/
• www.securitytracker.com — http://www.securitytracker.com/id/1038571