Microsoft Defender Link Following Vulnerability

Added to KEV
2026-05-20
Federal due date
2026-06-03
Vendor
Microsoft
Product
Defender
EPSS
93.0th percentile (score 0.095, as of 2026-06-08)
NVD CVSS v3.1
7.8 (HIGH)
Ransomware use
Unknown
Upstream
https://nvd.nist.gov/vuln/detail/CVE-2026-41091

CISA short description

Microsoft Defender contains a link following vulnerability that allows an authorized attacker to elevate privileges locally.

Required action

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

NVD description

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

EPSS percentile is the FIRST.org exploit-probability ranking as of the date noted above; it moves daily. CVSS reflects NVD's analysis at time of publication.