Session Replay Attack Allows Authentication Bypass via Captured Login Responses Allowing Bypass of 429 Too many attempts for Multiple Failed Logins

Disclosed: 2025-05-01 19:33:10 By ctrl_cipher To wakatime
High
Vulnerability Details
#Summary An attacker can bypass authentication by capturing a valid login response (including session cookies/tokens) and replaying it during a failed login attempt with incorrect credentials. The server fails to invalidate or validate session tokens properly, allowing unauthorized access even after logout. #Steps to Reproduce 1. Legitimate Login: Send a valid login request (correct email/password). Capture the response using Burp Suite and copy it. 2. Invalid Login: Log out the user. Send a new login request with an incorrect password. Replace the 400 Bad Request response with the previously captured legitimate login response (including the valid session cookie). 3. Result: The server grants access to the account despite the wrong password. The attacker can now interact with the account as the legitimate user. #Recommendations Server-Side Session Invalidation: Maintain a database of active sessions and revoke old tokens on logout or failed login attempts. Token Binding: Bind session tokens to user context (e.g., IP address, user agent hash). Short-Lived Tokens: Use JWT with short expiration times (e.g., 15 minutes) and refresh tokens. Replay Attack Mitigation: Add a unique nonce or timestamp to each login request. Secure Cookie Attributes: Ensure cookies include Secure, HttpOnly, SameSite=Strict, and Max-Age ## Impact Unauthorized Account Access: Attackers can compromise any account by replaying captured session tokens. Persistence: Old tokens remain valid indefinitely. Data Theft/Abuse: Sensitive user data (coding activity, API keys, etc.) can be stolen or modified.
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Report Stats
  • Report ID: 3120790
  • State: Closed
  • Substate: informative
  • Upvotes: 1
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