A Checklist for Developing Defenses

Step	Description
Use a combined solution.	Use an Internet security solution that combines anti-virus, firewall, intrusion detection, and vulnerability management for maximum protection against blended threats.
Keep virus definitions updated.	By deploying the latest virus definitions, corporations and consumers are protected against the latest viruses known to be spreading "in the wild."
Turn off and remove unneeded services.	By turning off and removing unneeded services, you are decreasing the "attack surface" of a system, thereby reducing the number of potential vulnerabilities to which that system is exposed.
Block access to services when required.	If a blended threat exploits one or more network services, disable or block access to those services until a patch is applied.
Keep patch levels up to date.	Always keep your patch levels up to date, especially on computers that host public services and are accessible through the firewall, such as HTTP, FTP, mail, and DNS services.
Enforce a password policy.	Ensure that passwords are a mix of letters and numbers . Do not use dictionary words. Change passwords often.
Block suspicious attachments.	Configure your e-mail server to block or remove e-mail that contains file attachments that are commonly used to spread viruses.
Restrict hosts file.	Restrict access to your systems' hosts file in order to protect its contents and prevent malicious code from inserting malicious entries.
Isolate infected computers.	Once infected computers have been identified, it is important to immediately isolate them and remove them from the network in order to prevent further propagation.
Train employees .	Train employees not to open attachments unless they are expecting them. Also, do not execute software that is downloaded from the Internet unless it has been scanned for viruses.
Understand phishing scams.	All types of computer users need to know how to recognize computer hoaxes and phishing scams. Hoaxes typically include a bogus e-mail warning to "send this to everyone you know" and improper technical jargon to frighten or mislead users. Phishing scams are much more sophisticated. Often arriving in e-mail, phishing scams appear to come from a legitimate organization and entice users to enter credit card or other confidential information into forms on a web site designed to look like the legitimate organization. Consumers and business professionals also need to consider who is sending the information and determine if it is a reliable source. The best course of action is to simply delete these types of e-mails. Employees should be instructed to never forward these e-mails, and rather to contact their organization's security department if they have received such e- mails .
Create response procedures.	Ensure that emergency response procedures are in place to respond to an incident when it occurs.
Assess security.	Perform ongoing security assessments to ensure that adequate controls are in place.
Educate management.	Educate management on the need to provide an adequate security budget.

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