Authentication testing evaluates the security of identity verification processes to ensure only legitimate users gain access. It identifies vulnerabilities in credential handling, session management, and authentication logic.

Core Components of Authentication Testing

  1. Credentials Transported over Unencrypted Channel
     Definition: Testing whether login credentials (passwords, tokens) are transmitted without encryption (e.g., HTTP instead of HTTPS).
    Risk: Allows interception via man-in-the-middle (MITM) attacks.
  2. User Enumeration
     Definition: Identifying valid usernames/emails via error messages (e.g., “Invalid password” vs. “User not found”).
    Risk: Enables targeted brute-force attacks.
  3. Account Lockout
     Definition: Assessing if systems block users after repeated failed login attempts.
    Risk: Weak lockout policies permit brute-forcing; overly strict policies enable denial-of-service (DoS).
  4. Authentication Bypass
     Definition: Exploiting flaws (e.g., SQL injection, session tampering) to skip login steps.
    Risk: Grants unauthorized access to protected resources.
  5. “Remember Password” Functionality
     Definition: Testing how stored credentials (browser autofill, cookies) are secured.
    Risk: Persistent sessions or plaintext storage exposes credentials to theft.
  6. Browser Caching
     Definition: Checking if sensitive pages (post-login) are cached locally.
    Risk: Allows session hijacking via browser history or cache files.
  7. Weak Password Policy
     Definition: Evaluating password complexity rules (length, special characters).
    Risk: Predictable passwords (e.g., “Password123”) are easily cracked.
  8. Weak Password Security Mechanisms
     Definition: Testing for plaintext storage, insufficient hashing (MD5), or lack of salting.
    Risk: Database breaches expose reusable credentials.
  9. Weak Password Change/Reset Flow
     Definition: Assessing if reset links expire, use predictable tokens, or lack multi-factor confirmation.
    Risk: Allows account takeover via token reuse or social engineering.
  10. Race Conditions
     Definition: Exploiting timing flaws (e.g., parallel login attempts) to bypass rate limits.
    Risk: Enables credential stuffing or token duplication.
  11. Weak Multiple Factors Authentication (MFA)
     Definition: Testing MFA bypass via code reuse, SIM swapping, or insecure 2FA apps.
    Risk: Renders MFA ineffective against phishing or interception.
  12. Weak CAPTCHA Implementation
     Definition: Assessing if Captcha’s are easily solved by bots (e.g., static images, predictable logic).
    Risk: Fails to prevent automated attacks.
  13. Weaker Authentication in Alternative Channel
     Definition: Testing if SMS/email-based login lacks equivalent security to primary methods.
    Risk: Attackers exploit low-security channels for account access.