---
id: CVE-2026-116167
title: SiYuan 2.9.0 before 3.8.7 XSS via check-auth to Parameter
summary: >-
  SiYuan from 2.9.0 before 3.8.7 contains a cross-site scripting vulnerability
  in the unauthenticated /check-auth page that assigns the to parameter to
  window.location.href without scheme validation. Attackers can send a crafted
  link with …
severity: medium
cvss: 6.8
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N'
cvssSource: cna
cwe:
  - CWE-79
vendor: siyuan-note
product: siyuan
affected:
  - siyuan >= 2.9.0 < 3.8.7
published: '2026-10-25'
updated: '2026-10-25'
sourceUpdated: '2026-10-25T13:20:10.372Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-116167'
references:
  - url: >-
      https://github.com/siyuan-note/siyuan/security/advisories/GHSA-fmj3-xc2f-6w4w
    label: GitHub Security Advisory (GHSA-fmj3-xc2f-6w4w)
  - url: >-
      https://www.vulncheck.com/advisories/siyuan-2.9.0-before-3.8.7-xss-via-check-auth-to-parameter
    label: >-
      VulnCheck Advisory: SiYuan 2.9.0 before 3.8.7 XSS via check-auth to
      Parameter
tags:
  - cve.org
ingestedAt: '2026-10-25T22:08:29.948Z'
---

## Overview

SiYuan from 2.9.0 before 3.8.7 contains a cross-site scripting vulnerability in the unauthenticated /check-auth page that assigns the to parameter to window.location.href without scheme validation. Attackers can send a crafted link with a javascript: URI that executes after victim login, invoking kernel APIs to read or modify workspace content and settings.

## Affected

- `siyuan >= 2.9.0 < 3.8.7`

## Remediation

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