Why are short-lived, dynamic secrets in Vault more secure than long-lived, static credentials?

Comprehensive and Detailed In-Depth Explanation:

Short-lived, dynamic secrets in Vault enhance security by being generated on-demand and expiring after a short, configurable time-to-live (TTL). This reduces the window of opportunity for credential leakage or misuse. Unlike long-lived, static credentials, which persist indefinitely and increase exposure risk if compromised, dynamic secrets are ephemeral—once they expire, they’re automatically revoked by Vault, rendering them useless to attackers. For example, a database credential might last 5 minutes, limiting its attack surface compared to a static password stored indefinitely.

Option A (performance via caching) is unrelated to security and inaccurate, as dynamic secrets aren’t cached longer. Option C (eliminating authentication) is false; authentication is still required to obtain dynamic secrets. Option D (automatic rotation) applies to some dynamic secrets (e.g., database roles), but the core security benefit is their short lifespan, not just rotation. Vault’s documentation on dynamic secrets emphasizes their ephemerality as the key security advantage.