Comprehensive and Detailed Explanation:
* Understanding the Security Event:
* Unauthorized users gained access from non-production to production.
* IAM policies were weak, allowing bulk user creation.
* Vulnerability assessments were disabled, and patching was delayed.
* Logs were unavailable, making incident response difficult.
* Why Options A, D, and E are Correct:
* A (Disable bulk user creation by IAM team) # Prevents unauthorized mass user account creation, which could be exploited by attackers.
* D (Routine updates for endpoints & network devices) # Patch management ensures vulnerabilities are not left open for attackers.
* E (Ensure all security/network devices send logs to SIEM) # Helps with real-time monitoring and detection of unauthorized activities.
* Why Other Options Are Incorrect:
* B (180-day log retention) # While log retention is good, real-time monitoring is the priority.
* C (Review application allow list daily) # Reviewing it daily is impractical. Regular audits are better.
* F (Restrict production-to-non-production traffic) # The issue is unauthorized access, not traffic routing.