CISM Certified Information Security Manager – Question0473

The main mail server of a financial institution has been compromised at the superuser level; the only way to ensure the system is secure would be to:

A.
change the root password of the system.
B. implement multifactor authentication.
C. rebuild the system from the original installation medium.
D. disconnect the mail server from the network.

Correct Answer: C

Explanation:

Explanation:
Rebuilding the system from the original installation medium is the only way to ensure all security vulnerabilities and potential stealth malicious programs have been destroyed. Changing the root password of the system does not ensure the integrity of the mail server. Implementing multifactor authentication is an aftermeasure and does not clear existing security threats. Disconnecting the mail server from the network is an initial step, but does not guarantee security.