---
id: CVE-2026-100637
title: >-
  SiYuan versions before v3.8.4 contain a path traversal vulnerability in the
  checkoutRepo endpoint that allows authenticated administrators to write JSON
  files outside the workspace
summary: >-
  SiYuan versions before v3.8.4 contain a path traversal vulnerability in the
  checkoutRepo endpoint that allows authenticated administrators to write JSON
  files outside the workspace. Attackers can supply a sessionID parameter
  containing d…
severity: high
cvss: 7.6
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:N/I:H/A:L'
cwe:
  - CWE-73
vendor: siyuan-note
product: siyuan
affected:
  - siyuan < 3.8.4
published: '2026-09-26'
updated: '2026-09-26'
sourceUpdated: '2026-09-26T14:16:45.433'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-100637'
references:
  - url: >-
      https://github.com/siyuan-note/siyuan/security/advisories/GHSA-jhmh-hr4g-c5g2
    label: disclosure@vulncheck.com
  - url: >-
      https://www.vulncheck.com/advisories/siyuan-before-3.8.4-path-traversal-via-checkoutrepo-sessionid
    label: disclosure@vulncheck.com
tags:
  - nvd
  - cve.org
ingestedAt: '2026-09-26T13:33:20.924Z'
---

## Overview

SiYuan versions before v3.8.4 contain a path traversal vulnerability in the checkoutRepo endpoint that allows authenticated administrators to write JSON files outside the workspace. Attackers can supply a sessionID parameter containing directory traversal sequences to overwrite arbitrary JSON files in pre-existing kernel-writable directories outside workspace boundaries.

## Remediation

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