Beware What is Hiding Behind that Shortened URL
If you have ever tried to copy and paste a URL from a web site to share with a friend in an email you may have noticed that some of those suckers are LONG! They’re filled with coded gibberish that only make sense or matters to the web server delivering the content to you. The explosion of Twitter– which limits messages to a maximum of 140 characters, URL included– has made the length of URL’s an even more relevant issue.
Fear not! Services like Bit.ly and TinyURL have sprung up to solve the problem. These services take whatever URL you throw at them and convert it to a much shorter alias URL. For example, I entered ‘http://www.tonybradley.com’ into Bit.ly and got the shortened URL ‘http://bit.ly/A5RCi‘.
That works great for fitting the URL into Twitter, but it poses an issue from a security perspective. One of the simplest deterrents to malicious websites and phishing attacks is to simply look at the URL you are clicking on and apply an ounce of common sense. You can’t do that when the URL you are clicking on is a shortened alias of gibberish that has nothing to do with the actual destination web site.
For instance, if you receive an email allegedly from Customer Service at Bank of America and you actually have an account at Bank of America you might actually be tempted for a second to click on the link. But, when you see that the link in the email goes to ‘http://www.bankofamerica.com.sadisticattacker.is/Iplantotakeyourmoney’ you realize that the request is not legitimate.
But, when I take that exact same URL and enter it into Bit.ly I get ‘http://bit.ly/3nR6gq’. With a shortened URL like this one there is no way to tell just by looking at it whether it is legitimate or malicious.
Twitter users who use Tweetdeck have a security control to help out. Tweetdeck has a setting to ’show preview information for short URL’s’. When you click on a short URL a pop-up window appears which displays the short URL, the real URL it leads to, and the title of the destination web page so you can make an informed decision about whether or not to follow through and visit the site.
That is great for Twitter users….at least those who use Tweetdeck. The rest of you on your own though. Make sure you keep your system patched and updated and that you are running some type of antimalware protection on your PC just in case you click on the wrong URL. Think twice about the source of shortended URL’s and always remember Step #1 of the 5 Steps to Protect Yourself From Phishing Scams: BE SKEPTICAL!