How severe is CVE-2026-41091?

CVE-2026-41091 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-41091 being actively exploited?

Yes. CVE-2026-41091 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2026-05-20, which means active exploitation has been confirmed. It should be prioritised for remediation.

What products are affected by CVE-2026-41091?

CVE-2026-41091 affects Microsoft Malware Protection Engine. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-41091?

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-2026-41091 have an EU (EUVD) identifier?

Yes. CVE-2026-41091 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-31101. It is also flagged as exploited in the EUVD (since 2026-05-20).

When was CVE-2026-41091 published?

CVE-2026-41091 was published on 2026-05-20 and last updated on 2026-06-17.

CVE-2026-41091

CVE-2026-41091 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 2026-05-20). The underlying weakness is classified as CWE-59.

Key facts

Severity: High (CVSS 3.x base score 7.8)
EPSS exploit prediction: 8% (94th percentile)
Actively exploited: Yes — listed in CISA KEV (added 2026-05-20)
EU (EUVD) id: EUVD-2026-31101
EU exploitation: Flagged exploited in the ENISA EU Vulnerability Database (since 2026-05-20)
Weakness: CWE-59
Affected product: Microsoft Malware Protection Engine
Published: 2026-05-20
Last modified: 2026-06-17

Description

Improper link resolution before file access ('link following') in Microsoft Defender allows an authorized attacker to elevate privileges locally.

Frequently asked questions

What is CVE-2026-41091?: Improper link resolution before file access ('link following') in Microsoft Defender allows an authorized attacker to elevate privileges locally.
How severe is CVE-2026-41091?: CVE-2026-41091 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-41091 being actively exploited?: Yes. CVE-2026-41091 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2026-05-20, which means active exploitation has been confirmed. It should be prioritised for remediation.
What products are affected by CVE-2026-41091?: CVE-2026-41091 affects Microsoft Malware Protection Engine. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-41091?: 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-2026-41091 have an EU (EUVD) identifier?: Yes. CVE-2026-41091 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-31101. It is also flagged as exploited in the EUVD (since 2026-05-20).
When was CVE-2026-41091 published?: CVE-2026-41091 was published on 2026-05-20 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:microsoft:malware_protection_engine:*:*:*:*:*:*:*:*

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