---
id: CVE-2026-116171
title: >-
  SiYuan 3.5.4 before 3.8.7 Sensitive Path Bypass via Windows Extended-Length
  Prefix
summary: >-
  SiYuan 3.5.4 before 3.8.7 on Windows contains a sensitive-path denylist bypass
  in IsSensitivePath because the Windows extended-length prefix (\\?\) survives
  filepath.Clean and matches no forbidden prefix. Authenticated API callers can
  pr…
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N'
cvssSource: cna
cwe:
  - CWE-22
vendor: siyuan-note
product: siyuan
affected:
  - siyuan >= 3.5.4 < 3.8.7
published: '2026-10-25'
updated: '2026-10-25'
sourceUpdated: '2026-10-25T14:27:43.223Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-116171'
references:
  - url: >-
      https://github.com/siyuan-note/siyuan/security/advisories/GHSA-6gmc-424x-xgpm
    label: GitHub Security Advisory (GHSA-6gmc-424x-xgpm)
  - url: >-
      https://www.vulncheck.com/advisories/siyuan-3.5.4-before-3.8.7-sensitive-path-bypass-via-windows-extended-length-prefix
    label: >-
      VulnCheck Advisory: SiYuan 3.5.4 before 3.8.7 Sensitive Path Bypass via
      Windows Extended-Length Prefix
tags:
  - cve.org
ingestedAt: '2026-10-25T22:08:29.935Z'
---

## Overview

SiYuan 3.5.4 before 3.8.7 on Windows contains a sensitive-path denylist bypass in IsSensitivePath because the Windows extended-length prefix (\\?\) survives filepath.Clean and matches no forbidden prefix. Authenticated API callers can prepend the prefix to localPath in /api/import/importStdMd to copy workspace conf files, including the API token and TLS private keys, into assets served to unauthenticated clients.

## Affected

- `siyuan >= 3.5.4 < 3.8.7`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.