Hacking For Dummies®, 2nd Edition

Chapter 14. Messaging Systems

In This Chapter

• Attacking e-mail systems

• Assailing instant messaging

• Assaulting Voice over IP applications

Messaging systems — you know, those e-mail, instant messaging (IM), and Voice over IP (VoIP) applications that we all depend on — are often hacked within a network. Why? Well, from my experience, messaging software — both at the server and client level — is vulnerable because network administrators often believe that antivirus software is all that's needed to keep trouble away, ignore the existing security vulnerabilities, or simply forget about securing these systems altogether.

In this chapter, I show you how to test for common e-mail, IM, and VoIP issues. I also outline key countermeasures to help prevent these hacks against your systems.

Messaging System Vulnerabilities

Practically all messaging applications are hacking targets on your network. In fact, e-mail systems are some of the most targeted. Given the proliferation and business value of IM and other P2P applications, attacks against networks launched via IM channels will be at least as common as e-mail attacks. Wondering about VoIP? Well, it's downright scary what hackers can do with it.

A ton of vulnerabilities are inherent in messaging systems. The following factors can create weaknesses:

• Security is rarely integrated into software development.

• Convenience and usability often outweigh the need for security.

• Many of the messaging protocols weren't designed with security in mind — especially those ...