Portswigger
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  • SSRF with filter bypass via open redirection vulnerability
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    • Cross-Site Scripting (XSS)
  • Reflected XSS into a JS string with angle brackets and double&single quotes HTML-encoded escape
  • XSS into a template literal w/ angle brackets, single, double quotes, backslash & backticks Escaped
  • Authentication
    • Authentication
  • Username enumeration via subtly different responses
  • 2FA broken logic
  • Username enumeration via response timing
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  • Password reset poisoning via middleware
  • Path Traversal
    • Path Traversal
  • File path traversal, traversal sequences stripped with superfluous URL-decode
  • File path traversal, traversal sequences blocked with absolute path bypass
  • Business Logic Vulnerabilities
    • Business Logic Vulnerabilities
  • Insufficient workflow validation
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  • Server-Side Template Injection
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  • Basic server-side template injection
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    • Blind SQL injection with conditional responses
  • SQL injection UNION attack, retrieving data from other tables
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  • API Testing
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  • Exploiting an API endpoint using documentation
  • Exploiting a mass assignment vulnerability
  • Finding and exploiting an unused API endpoint
  • JWT ATTACK
    • JWT Attack
    • JWT authentication bypass via unverified signature
  • JWT authentication bypass via jku header injection
  • JWT authentication bypass via flawed signature verification
  • HTTP HOST HEADER ATTACKS
    • HTTP Host header attacks
  • Basic password reset poisoning
  • Host header authentication bypass
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  • Detecting NoSQL injection
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  • FILE UPLOAD VULNERABILITIES
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  • OAuth Authentication
    • OAuth Authentication
  • OAuth account hijacking via redirect_uri
  • ACCESS CONTROL VULNERABILITIES
    • Access Control Vulnerabilities
  • User ID controlled by request parameter with data leakage in redirect
  • User ID controlled by request parameter with password disclosure
  • User role controlled by request parameter
  • User role can be modified in user profile
  • URL-based access control can be circumvented
  • INFORMATION DISCLOSURE VULNERABILITIES
    • Information Disclosure Vulnerabilities
  • Information disclosure in version control history
  • XML external entity injection
    • XML External Entity (XXE) Injection
  • Exploiting XXE using external entities to retrieve files
  • Exploiting blind XXE to retrieve data via error messages
  • Blind XXE with out-of-band interaction
  • Blind XXE with out-of-band interaction via XML parameter entities
  • OS COMMAND INJECTION
    • OS Command Injection
  • Blind OS command injection with out-of-band data exfiltration
  • PROTOTYPE POLLUTION
    • Prototype Pollution
  • Privilege escalation via server-side prototype pollution
  • WEB CACHE POISONING
    • Web Cache Poisoning
  • Web cache poisoning via an unkeyed query parameter
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  1. JWT ATTACK

JWT authentication bypass via unverified signature

Link: https://portswigger.net/web-security/jwt/lab-jwt-authentication-bypass-via-unverified-signature

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Last updated 3 months ago

Description:

This lab uses a JWT-based mechanism for handling sessions. Due to implementation flaws, the server doesn't verify the signature of any JWTs that it receives.

To solve the lab, modify your session token to gain access to the admin panel at /admin, then delete the user carlos.

You can log in to your own account using the following credentials: wiener:peter

Preparation:

  • Install JWT Editor on Burp Suite Extension

Proof of concept:

  1. Analisa seluruh fitur web target menggunakan akun testing

  2. Dari pengumpulan informasi didapati terdapat direktori /admin

  3. Akses halaman /admin. Terlihat halaman /admin hanya dapat diakses oleh administrator

  4. Dapat dilihat pada web target ini menggunakan JWT, analisa JWT yang diberikan ketika login menggunakan akun testing. Kirim request pada saat mengakses /admin ke burp repeater

  5. Buka tab JSON Web Token. Pada payload terlihat terdapat parameter sub dengan nilai wiener. Parameter tersebut berisikan nilai username yang sedang login

  6. Ubah nilai pada parameter sub tersebut menjadi administrator. Jika sudah lakukan sign dengan Header Options Don’t modify header

  7. Kirim kembali request untuk mengakses /admin. Dapat dilihat sebelumnya status code pada saat mengakses /admin adalah 401 sekarang menjadi 200 yang artinya sudah dapat mengakses halaman /admin. Untuk menyelesaikan tangtangan pada lab ini lakukan penghapusan user carlos

Thanks, Stay Ethical & Happy Hacking! 🍻