VulnerabilityDeferred

CVE-2026-74801

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.

HIGH 8.6EPSS 0.27%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.27%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

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.

CVSS 4.0: 8.6 HIGHCVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:P/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
EPSS: 0.27% probability · 18th percentile
CISA KEV: Not listed
Weakness: CWE-78
Source: disclosure@vulncheck.com

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.