SiYuan is a personal knowledge management system. Prior to version 3.5.5, the /api/file/copyFile endpoint does not validate the dest parameter, allowing authenticated users to write files to arbitrary locations on the filesystem. This can lead to Remote Code Execution (RCE) by writing to sensitive locations such as cron jobs, SSH authorized_keys, or shell configuration files. This issue has been patched in version 3.5.5.
History

Wed, 04 Feb 2026 22:00:00 +0000

Type Values Removed Values Added
Description SiYuan is a personal knowledge management system. Prior to version 3.5.5, the /api/file/copyFile endpoint does not validate the dest parameter, allowing authenticated users to write files to arbitrary locations on the filesystem. This can lead to Remote Code Execution (RCE) by writing to sensitive locations such as cron jobs, SSH authorized_keys, or shell configuration files. This issue has been patched in version 3.5.5.
Title SiYuan has Arbitrary File Write via /api/file/copyFile leading to RCE
Weaknesses CWE-22
References
Metrics cvssV3_1

{'score': 9.1, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H'}


cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-02-04T21:39:12.438Z

Reserved: 2026-02-02T19:59:47.374Z

Link: CVE-2026-25539

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-02-04T22:16:00.083

Modified: 2026-02-04T22:16:00.083

Link: CVE-2026-25539

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.