Advanced Token Management Strategies

Token management is a critical component of web application security. This lesson focuses on advanced strategies for managing authentication tokens, particularly in the front-end context. Understanding these strategies helps mitigate risks associated with token theft and session hijacking.

2.1 Storage Options

Tokens can be stored in:

• Local Storage
• Session Storage
• Cookies

Each option has its pros and cons:

• Local Storage: Persistent but vulnerable to XSS attacks.
• Session Storage: Scoped to the session but also vulnerable to XSS.
• Cookies: Can be made HTTP-only, mitigating XSS risks.

3.1 Purpose and Usage

Refresh tokens are used to obtain new access tokens without requiring the user to re-authenticate. This increases security by limiting the lifespan of access tokens.

3.2 Implementation Steps

1. When the user logs in, issue both an access token and a refresh token.
2. Store the refresh token securely (preferably in an HTTP-only cookie).
3. When the access token expires, use the refresh token to request a new access token.

4.1 Short-Lived Access Tokens

Implement short-lived access tokens (e.g., 15 minutes) to minimize the impact of token theft.

4.2 Grace Periods

Allow a grace period for token renewal to avoid forcing the user to log in unexpectedly.

• Always use HTTPS to protect tokens in transit.
• Implement Content Security Policy (CSP) to mitigate XSS attacks.
• Use secure, HTTP-only cookies for storing tokens.
• Regularly rotate refresh tokens and invalidate old ones.