CVE-2026-25539— SiYuan has Arbitrary File Write via /api/file/copyFile leading to RCE
Possible ATT&CK Techniques 3AI
T1059 · Command and Scripting Interpreter T1505 · Server Software Component T1546 · Event Triggered ExecutionGet alerts for future matching vulnerabilitiesLog in to subscribe
I. Basic Information for CVE-2026-25539
Vulnerability Information
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Vulnerability Title
SiYuan has Arbitrary File Write via /api/file/copyFile leading to RCE
Source: NVD (National Vulnerability Database)
Vulnerability 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.
Source: NVD (National Vulnerability Database)
CVSS Information
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
Source: NVD (National Vulnerability Database)
Vulnerability Type
对路径名的限制不恰当(路径遍历)
Source: NVD (National Vulnerability Database)
Vulnerability Title
SiYuan 路径遍历漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
SiYuan是SiYuan开源的一个隐私至上的个人知识管理系统。 SiYuan 3.5.5之前版本存在路径遍历漏洞，该漏洞源于/api/file/copyFile端点未验证dest参数，可能导致写入文件至任意位置，进而引发远程代码执行。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)
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Affected Products
| Vendor | Product | Affected Versions | CPE | Subscribe |
|---|---|---|---|---|
| siyuan-note | siyuan | < 3.5.5 | - |
II. Public POCs for CVE-2026-25539
| # | POC Description | Source Link | Shenlong Link |
|---|
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Vendor Advisories for CVE-2026-25539 (1)
IV. Related Vulnerabilities
Same product: siyuan
- CVE-2026-44670
SiYuan: Stored XSS via Attribute View name to Electron rende - CVE-2026-44588
SiYuan: URL-encoded title bypasses `escapeAriaLabel`, decode - CVE-2026-45147
SiYuan: Broken access control in SiYuan `/api/tag/getTag` — - CVE-2026-45148
SiYuan: Broken access control in SiYuan publish-mode Readers - CVE-2026-45371
SiYuan: SiYuan publish-mode Reader can mutate Conf and SQL i
Same vendor: siyuan-note
- CVE-2026-44670
SiYuan: Stored XSS via Attribute View name to Electron rende - CVE-2026-44588
SiYuan: URL-encoded title bypasses `escapeAriaLabel`, decode - CVE-2026-45147
SiYuan: Broken access control in SiYuan `/api/tag/getTag` — - CVE-2026-45148
SiYuan: Broken access control in SiYuan publish-mode Readers - CVE-2026-45371
SiYuan: SiYuan publish-mode Reader can mutate Conf and SQL i
Same weakness: CWE-22
- CVE-2026-45571
go-git: Crafted repositories may modify main and submodule . - CVE-2026-48544
Taipy 4.1.1 Path Traversal via ElementLibrary.get_resource() - CVE-2026-6957
Path traversal in Mattermost Legal Hold plugin via unsanitiz - CVE-2026-47118
Agent Zero < 1.15 Path Traversal File Read via image_get API - CVE-2026-9035
Multiple vulnerabilities in Aspera applications.
V. Comments for CVE-2026-25539
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