How severe is CVE-2017-8540?

CVE-2017-8540 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2017-8540 being actively exploited?

Yes. CVE-2017-8540 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2022-03-03, which means active exploitation has been confirmed. It should be prioritised for remediation.

What products are affected by CVE-2017-8540?

CVE-2017-8540 primarily affects Microsoft Malware Protection Engine. In total, 11 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2017-8540?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.

Does CVE-2017-8540 have an EU (EUVD) identifier?

Yes. CVE-2017-8540 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2017-17490. It is also flagged as exploited in the EUVD (since 2022-03-03).

When was CVE-2017-8540 published?

CVE-2017-8540 was published on 2017-05-26 and last updated on 2026-06-17.

CVE-2017-8540

CVE-2017-8540 is a high-severity vulnerability in Microsoft Malware Protection Engine with a CVSS 3.x base score of 7.8. It is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, confirming it has been exploited in the wild (added 2022-03-03). The underlying weakness is classified as CWE-787.

Key facts

Severity: High (CVSS 3.x base score 7.8)
CVSS v2: 9.3
EPSS exploit prediction: 72% (99th percentile)
Actively exploited: Yes — listed in CISA KEV (added 2022-03-03)
EU (EUVD) id: EUVD-2017-17490
EU exploitation: Flagged exploited in the ENISA EU Vulnerability Database (since 2022-03-03)
Weakness: CWE-787
Affected product: Microsoft Malware Protection Engine
Published: 2017-05-26
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2017-8540?: 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.
How severe is CVE-2017-8540?: CVE-2017-8540 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2017-8540 being actively exploited?: Yes. CVE-2017-8540 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2022-03-03, which means active exploitation has been confirmed. It should be prioritised for remediation.
What products are affected by CVE-2017-8540?: CVE-2017-8540 primarily affects Microsoft Malware Protection Engine. In total, 11 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2017-8540?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.
Does CVE-2017-8540 have an EU (EUVD) identifier?: Yes. CVE-2017-8540 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2017-17490. It is also flagged as exploited in the EUVD (since 2022-03-03).
When was CVE-2017-8540 published?: CVE-2017-8540 was published on 2017-05-26 and last updated on 2026-06-17.

References

Affected products (11)

cpe:2.3:a:microsoft:malware_protection_engine:*:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:endpoint_protection:-:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:exchange_server:2013:-:*:*:*:*:*:*
cpe:2.3:a:microsoft:exchange_server:2016:-:*:*:*:*:*:*
cpe:2.3:a:microsoft:forefront_endpoint_protection:-:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:forefront_endpoint_protection:2010:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:forefront_security:-:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:intune_endpoint_protection:-:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:security_essentials:-:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:system_center_endpoint_protection:-:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:windows_defender:-:*:*:*:*:*:*:*

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