A new security risk has been discovered within Adobe Acrobat reader that can make your computer susceptible to hijacking and data theft. The issue has to do with embedded JavaScript links in .pdf documents that are stored on computers.

There is a possibility that stored Acrobat PDF documents with malicious links can be secretly “connected” to an unscrupulous website, even when the document is not open. This connection could easily allow a criminal to have complete access to everything on your computer. If an intruder has complete and unrestricted access to your computer, he can easily steal files, access your online accounts, and install other software that will give him even more control. All this could be done without your knowledge – that’s the scary part!

There is no real way to tell if any of your saved .pdf documents include any of these unscrupulous links. Since these links are written using JavaScript, they are not considered “spyware” or a “computer virus”, so antispyware and antivirus software will not detect any tainted .pdf files.

Adobe Acrobat documents (and any other type of document, really) with embedded malicious links can easily get on your computer. Tainted files usually look just like any other file, and are commonly downloaded from “suspicious” websites or received as attachments via email. As a general rule of thumb - never download, save, or open any documents from people you don’t know or websites you don’t trust.

According to an article on Zdnet News, Adobe has been made aware of this potential security risk but has not yet verified that a hijacking attack like this could happen. Adobe suggests that people upgrade to the newest version of the popular (and free) Acrobat Reader, which is version 8.

Use Up-To-Date Software

Because new security threats like this one are discovered on a regular basis, it’s always a good idea to ensure you are running the most current version of every software program. The most current versions of software are always the safest, and it’s usually free to upgrade.

This advice applies to Internet Explorer too, which is the world’s most popular web browser. If you are not yet using Internet Explorer version 7, you should upgrade now. You can easily check the version of any software by clicking on “Help” from within the program, then clicking “About”.

The internet has become a very dangerous place, and it’s important for everyone to protect themselves with up-to-date security software and knowledge about the various security threats (and potential threats) that exist. Since the net is the world’s largest community with over a billion computers online, there are probably a few million criminals online just waiting for an innocent victim who isn’t taking security precautions.

For more information on internet security and what you can do to protect yourself online, you may be interested in this free report called “Internet Crime – How to Protect Yourself Online”. This report was written by me, and I give it to all subscribers of my newsletter: “Computer Security Tips”. My monthly newsletter is really more like a “course in computer security, in easy-to-understand language. Each issue focuses on only one computer security topic, and covers “just the facts” and “what you need to know” to stay safe online.