What is a security patch, and why is it important? A security patch is a small program that updates a larger program with the goal of sealing off a vulnerability that can allow the program to be attacked. There are many possible ways a program can be attacked. In some cases, the security patch will block a denial of service. Generally reserved for high profile sites, denial of service attacks can also victimize individual computers. The attack generally causes the intended program to not function, or denies you from access to the network or internet. As new ways for hackers to accomplish this are discovered, a security patch is written and released to repair the opening that could allow an attack.
Other holes repaired by a security patch are ones that allow a hacker to assume some aspect of control over a computer, either by access to files and personal data, or even the ability to view what is happening on your screen and execute programs. The exploits are often distributed by trojans, which are malicious programs similar to viruses but require a user to execute them in order to infect the machine. A security patch will close holes that trojans take advantage of. The trojan can still be launched and still infect the system, however, the security patch will prevent it from operating as the hacker intended. It will not be able to perform the malicious function that it was designed to do.
Keeping all your programs updated to the latest security patch level is vital. So much focus is put on virus protection software that sometimes maintaining security patch levels falls behind. Virus updates are also important, but not all attacks come in the form of a viral infection. Keeping up with the latest security patch for your applications and your operating system will keep your computer well rounded in its security.