Vulnerability · Published Aug 30, 2026 · Assigned by VulnCheck
CVE-2026-82649SiYuan before 3.8.1 Local Privilege Escalation via Uncontrolled Search Path
High 7.0
In plain English
A high-severity uncontrolled search path in siyuan from siyuan-note. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 7% of all known vulnerabilities).
Official description
SiYuan Windows installer before version 3.8.1 (affected versions >= 2.0.14) contains an uncontrolled search path element vulnerability in its NSIS installer, which invokes system executables such as TASKKILL by name rather than by absolute path. Because NSIS nsExec::Exec resolves these calls using a search path that includes the installer's own launch directory ahead of System32, an attacker who plants a malicious executable (e.g., a renamed TASKKILL.exe) in that directory can have it executed when the installer runs. These calls occur in electron-builder's preInit hook before the license page is displayed, and with an all-users (elevated) install the planted binary executes with an elevated token, resulting in local privilege escalation.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| siyuan-note | siyuan | 2.0.14 – before 3.8.1 |
Weakness: CWE-427 · Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
References
- GitHub Security Advisory (GHSA-9j65-967f-5rv3) vendor-advisory
- Patch Commit patch
- VulnCheck Advisory: SiYuan before 3.8.1 Local Privilege Escalation via Uncontrolled Search Path third-party-advisory