Which is the description of CSRF (Cross-Site Request Forgery)?

CSRF is a security vulnerability where an attacker tricks an authenticated user into performing unwanted actions on a different website without their knowledge or consent. The original options A, C, and D describe XSS (cross-site scripting), clickjacking, or other attacks—not CSRF. Option B accurately captures the core mechanism: exploiting a user's active session to forge malicious requests.

Step-by-step Derivation:
CSRF fundamentals: (1) Attacker creates a malicious site/link; (2) Victim visits while logged into target site; (3) Victim's browser automatically includes authentication cookies; (4) Unwanted request executes with victim's privileges. This differs from XSS (code injection) or other web attacks. The provided options A, C, D are poorly worded, so option B was reconstructed as the standard CSRF definition.