CVE-2026-74801

HIGH CVSS 4.0: 8.6 EPSS 0.27%
Updated Aug 17, 2026
Microsoft
Parameter Value
CVSS 8.6 (HIGH)
Affected Versions before 3.7.4
Type CWE-78 (OS Command Injection)
Vendor Microsoft
Public PoC No

SiYuan before 3.7.4 fails to properly escape workspace directory paths when constructing command-line arguments for the elevated elevator.exe helper process. Attackers can create a malicious workspace directory with command metacharacters in its path and trigger the Microsoft Defender exclusion flow to execute arbitrary commands with administrator privileges after UAC approval.

Attack Parameters

Attack Vector
Local
Requires local access
Attack Complexity
Low
Easy to exploit
Attack Requirements
None
No additional conditions
Privileges Required
Low
Basic privileges needed
User Interaction
Passive
Minimal interaction

Impact Assessment

Confidentiality
High
Complete data leak
Integrity
High
Complete data modification
Availability
High
Complete denial of service

CVSS Vector v4.0

Weakness Type (CWE)