Hacking For Dummies® 3rd Edition

Chapter 13. Communication and 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 — often create vulnerabilities that people overlook. Why? Well, from my experience, messaging software — both at the server and client level — is vulnerable because network administrators often believe that firewalls and antivirus software are all that's needed to keep trouble away, or they 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. 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 are about as common as e-mail attacks. Wondering about VoIP? Well, it's downright scary what people with ill intent can do with it.

Tons of vulnerabilities are inherent in messaging systems. This is because most messaging protocols weren't designed with security in mind — especially those developed several decades ago when security wasn't nearly the issue it is today. The funny thing is that even modern-day messaging protocols ...