CVE-2026-41091: Microsoft Defender

What is CVE-2026-41091?

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

CVSS7.8 NVD 3.1

SeverityHIGH

Exploitation In the wild In CISA KEV

EPSS10% · P95

Triage statusActive Exploit

ActionPatch immediately

CVSS vectorCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

NVD published2026-05-20

NVD last modified2026-07-24

Timeline

2026-05-20Published to the U.S. National Vulnerability Database (NVD)
2026-05-20Added to the CISA Known Exploited Vulnerabilities (KEV) catalog
2026-05-22First covered in a defend.network daily briefing
2026-06-03CISA federal remediation deadline (BOD 22-01)
2026-07-24NVD record last updated

CISA Known Exploited Vulnerability

Microsoft Defender Link Following Vulnerability

Added to KEV2026-05-20

Federal patch deadline2026-06-03

Known ransomware useUnknown

Affected product

Microsoft Defender

References

Referenced in our briefings & reports

Critical RCEs: Microsoft Defender, Linux kernel, Cisco Workload; Showboat targets telcos (2026-05-22)

Browse all tracked CVEs in the defend.network CVE database →

🤖 This CVE page is generated by defend.network from NVD, CISA KEV, EPSS, and our verified daily briefings. Severity and exploitation data come from official sources; always verify remediation steps against the official vendor advisory before acting in production.