Heimdall - Host Header Injection & Open Redirect

id: CVE-2025-50578

info:
  name: Heimdall - Host Header Injection & Open Redirect
  author: DhiyaneshDk
  severity: medium
  description: |
    LinuxServer.io Heimdall 2.6.3-ls307 contains a host header injection caused by improper validation of user-supplied HTTP headers `X-Forwarded-Host` and `Referer`, letting unauthenticated remote attackers perform host header injection and open redirect attacks, exploit requires no special privileges.
  impact: |
    Unauthenticated attackers can redirect users to malicious sites, enabling phishing, UI redress, and session theft.
  remediation: |
    Update to the latest version of Heimdall.
  reference:
    - https://github.com/linuxserver/Heimdall/issues/1451
    - https://medium.com/@juanfelipeoz.rar/cve-2025-50578-exploiting-host-header-injection-open-redirect-in-heimdall-application-733afceff2ea
  metadata:
    verified: true
    max-request: 1
    shodan-query: html:"Heimdall"
  tags: cve,cve2025,heimdall,redirect,host-header,oos

http:
  - raw:
      - |
        GET / HTTP/1.1
        Host: {{Hostname}}
        X-Forwarded-Host: interact.sh

    matchers-condition: and
    matchers:
      - type: word
        part: body
        words:
          - '<script src="http://interact.sh/'
          - 'Heimdall'
        condition: and

      - type: status
        status:
          - 200
# digest: 4a0a00473045022100c9868fe6b485b6358c63428e38a08fac5bac18904dacd998c54c85cc41e53b6802204cf05b3bff06fcbaeb3ceaa160d4bf27bf71bb5a3ae47bf764c793d4fba541e7:922c64590222798bb761d5b6d8e72950