SB2026052118 - Privilege escalation in Microsoft Malware Protection Engine



SB2026052118 - Privilege escalation in Microsoft Malware Protection Engine

Published: May 21, 2026

Security Bulletin ID SB2026052118
CSH Severity
High
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Local access
Highest impact Code execution

Breakdown by Severity

High 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 vulnerability.


1) Link following (CVE-ID: CVE-2026-41091)

CWE-ID: CWE-59 - Improper Link Resolution Before File Access ('Link Following')

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:A/U:Amber


The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to an insecure link following issue. A local user can create a specially crafted symbolic link to a critical file on the system and overwrite it with elevated privileges.

Note, the vulnerability is being actively exploited in the wild. 


Remediation

Install update from vendor's website.