Microsoft Defender
CVE-2026-41091 — Microsoft Defender Elevation of Privilege Vulnerability
Executive Summary
Improper link resolution before file access ('link following') in Microsoft Defender allows an authorized attacker to elevate privileges locally.
Overview
7.8
CVSS HIGH
Important
MS Severity
Exploited
MS Exploit Status
Exploitation Detected
MS Exploit Likelihood
CVSS Vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
ATTACK VECTOR
Local
ATTACK COMPLEXITY
Low
PRIVILEGES REQUIRED
Low
USER INTERACTION
None
SCOPE
Unchanged
CONFIDENTIALITY
High
INTEGRITY
High
AVAILABILITY
High
EXPLOIT CODE MATURITY
Unproven
REMEDIATION LEVEL
Official Fix
REPORT CONFIDENCE
Confirmed
Temporal Score: 6.8
EPSS Score
0.09641
probability of exploitation in the next 30 days
0.95051 percentile - updated 2026-08-14
View on FIRST.org
Affected Products
1 affected product
| Product | KB Article | Severity | Impact | Restart Required |
|---|---|---|---|---|
| Microsoft Malware Protection Engine | Release Notes (Security Update) |
Important | Elevation of Privilege | No |
Patches
1 patch
| Article | Type | Restart |
|---|---|---|
Release Notes |
Security Update | No |
Exploits & PoC
4 public PoCsUnverified third-party code
Public proof-of-concept repositories aggregated from PoC-in-GitHub. They are not reviewed and may be incomplete, non-functional, or malicious — inspect the code before running anything.
| Repository | Stars | Published | Description |
|---|---|---|---|
| 0xBlackash/CVE-2026-41091 | 11 | 2026-05-21 | CVE-2026-41091 |
| tc4dy/CVE-2026-41091-PoC-Exploit | 3 | 2026-06-20 | CVE-2026-41091 RedSun | Microsoft Defender LPE exploit. Low-privileged users gain NT AUTHORITY\SYSTEM 🔥 via Cloud Files API + NTFS junction trickery. Forces Defender to write malicious payloads to Sys |
| s4m98/RedSun- | 1 | 2026-08-09 | Windwos Zero Day Local PrivESc Exploit (CVE-2026-41091) |
| ridhinva/defender-privilege-escalation-scanner | 0 | 2026-05-22 | Scanner: CVE-2026-41091/45498 Microsoft Defender LPE/DoS — Python scanner for Windows Defender privilege escalation (CISA KEV) |
Detection Rules
No public Sigma or Nuclei detection rule has been mapped to this CVE yet. Coverage is concentrated on exploited / high-profile vulnerabilities; check SigmaHQ for updates.
Acknowledgments
Damir Moldovanov
ACD421
Anonymous
Diffract
Sibusiso
References
On This Page