Based on the provided authentication logs, we observe that User1's account experienced multiple failed login attempts within a very short time span (at 8:01:23 AM on 12/15). This pattern indicates a potential brute-force attack or an attempt to gain unauthorized access. Here's a breakdown of why disabling User1's account is the appropriate first step:
Failed Login Attempts: The logs show that User1 had four consecutive failed login attempts:
VM01 at 8:01:23 AM
VM08 at 8:01:23 AM
VM01 at 8:01:23 AM
VM08 at 8:01:23 AM
Security Protocols and Best Practices: According to CompTIA Security+ guidelines, multiple failed login attempts within a short timeframe should trigger an immediate response to prevent further potential unauthorized access attempts. This typically involves temporarily disabling the account to stop ongoing brute-force attacks.
Account Lockout Policy: Implementing an account lockout policy is a standard practice to thwart brute-force attacks. Disabling User1's account will align with these best practices and prevent further failed attempts, which might lead to successful unauthorized access if not addressed.
Reference:
CompTIA Security+ SY0-601 Study Guide by Mike Chapple and David Seidl
CompTIA Security+ Certification Exam Objectives
NIST Special Publication 800-63B: Digital Identity Guidelines
By addressing User1's account first, we effectively mitigate the immediate threat of a brute-force attack, ensuring that further investigation can be conducted without the risk of unauthorized access continuing during the investigation period.