As you probably know, today's security is threatened by a huge number of hacker attacks conducted against vulnerable targets such as computers without powerful passwords or applications containing security flaws. Because some of the programs installed on a certain system can be affected by critical vulnerabilities, a successful exploitation of the issue can allow an attacker to control the computer or execute malicious commands. Most users think the flaws in the security system of the computer can be fixed with firewalls or an antivirus solution but, in some cases, a strong password is enough.

A recent study presented at the 37th Annual IEEE/IFIP International Conference on Dependable Systems and Networks sustained that hackers attack every 39 seconds, looking for computers with weak passwords or vulnerable applications. The research was based on four Linux based systems with weak protections and powerful Internet connection, the authors monitoring all the hacker attempts.

The authors mentioned hackers were using automated scripts that were trying to find the usernames and passwords using a large dictionary with millions of words and other combinations. After the program identified these two elements, hackers quickly changed the password, ran malicious programs or modified the configuration of the system. MSNBC News reported the most commonly used usernames were admin, guest, user, root and test while the most popular passwords were 123, password or 123456.

"Most of these attacks employ automated scripts that indiscriminately seek out thousands of computers at a time, looking for vulnerabilities. Our data provide quantifiable evidence that attacks are happening all the time to computers with Internet connections. Our data provide quantifiable evidence that attacks are happening all the time to computers with Internet connections," study author Michel Cukier of the University of Maryland sustained according to MSNBC News.

So, if you want to be 100 percent secure while your computer is connected to the Internet, you should use strong and long passwords containing both letters and numbers.