CVE-2026-82649

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.

CVSS

No CVSS.

References

Link	Resource
https://github.com/siyuan-note/siyuan/commit/251596fc0de2f9528c00c224252fd073a99973f4
https://github.com/siyuan-note/siyuan/security/advisories/GHSA-9j65-967f-5rv3
https://www.vulncheck.com/advisories/siyuan-before-3.8.1-local-privilege-escalation-via-uncontrolled-search-path
https://github.com/siyuan-note/siyuan/security/advisories/GHSA-9j65-967f-5rv3

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-30 15:16

Updated : 2026-09-01 15:17

NVD link : CVE-2026-82649

Mitre link : CVE-2026-82649

CVE.ORG link : CVE-2026-82649

JSON object : View

Products Affected

No product.

CWE

CWE-427

Uncontrolled Search Path Element

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