Hacking For Dummies® 3rd Edition

Chapter 11. Linux

In This Chapter

• Examining Linux hacking tools

• Port-scanning a Linux server

• Gleaning Linux information without logging in

• Exploiting common vulnerabilities when logged in to Linux

• Minimizing Linux security risks

Linux — the darling competitor to Microsoft — is the latest flavor of UNIX to take off in corporate networks. A common misconception is that the majority of security vulnerabilities are in the Windows operating system (OS). However, security experts see more and more that Linux and its sister variants of UNIX are prone to some of the same types of security vulnerabilities.

Hackers are attacking Linux in droves because of its popularity and growing usage in today's network environment. Because some versions of Linux are free — in the sense that you don't have to pay for the base operating system — many organizations are installing Linux for their Web servers and e-mail servers in hopes of saving money and having a more secure system. Linux has grown in popularity for other reasons as well, including the following:

• Abundant resources are available, including books, Web sites, and developer and consultant expertise.

• Unlikeliness that Linux will be hit with as much malware as Windows and its applications do. Linux excels when it comes to security, but it probably won't stay that way.

• Increased buy-in from other UNIX vendors, including IBM and Sun Microsystems. Even Novell stopped development of its mighty NetWare OS and is now focusing on a Linux-based kernel.

• Growing ...