There was a good post over at ThreatChaos the other day about a new Firefox extension which will automatically show you the real URL’s of shortened URL’s. What is URL shortening? For example…this long URL:
By using a service like Tinyurl or one of the many other sites available you can easily shorten a URL so your friends don’t freak when you send them long links. When it comes to Twitter it becomes almost mandatory that you shorten that long URL to meet the 140 character limit in your tweets.
What’s the problem?
Getting people to click on a malicious link just got easier with these services. Sure, people will still click on strange URL’s without a mask (even manually typing in strange URL’s as I showed in this post), however, by masking *any* URL with these services a phishing or malware attack can be even more successful.
Also, how can you *easily* see what the real site is behind one of these short URL’s? TinyURL and others offer you a service to “preview” URL’s but many sites don’t offer this and who is actually going to attempt to manually verify what is behind those links? That’s way too much work.
Another problem is that some of these short URL services allow you to obfuscate an already short URL with another short URL. Take for example Xrl.in. The TinyURL above (http://tinyurl.com/9lum95) becomes http://xrl.in/1b0i. This throws off the preview feature of many sites like this. This problem could add multiple redirects and levels of obfuscation to malicious links. All it takes is the right combination of short URL sites.
Right before I was about to post this I saw a post by Jennifer Leggio over at ZDNet regarding the URL redirection issue. She mentions that FriendFeed has implemented a feature that reveals short URL’s if you hover your mouse over the links. This is great…for FriendFeed, what about other more popular social media sites? Check out her article for a good overview of the issue and some interesting information about what other social media sites are doing and not doing about this problem.
The “Long URL Please” Solution
While not 100% perfect this a great start and it looks like the developer is working on improving the Firefox extension and API. You can even use it with other web browsers besides Firefox with a bookmarklet available on his site. Simply click on the bookmarklet and it will transform all the short URL’s on the web page currently loaded.
The Long URL Please Firefox extension will automatically show you the true URL of 30 supported short URL site’s. No hovering over a link or clicking to a site to preview it. It just shows you the link…no extra work on your part. This works great for the Twitter web client as well as any web page that has a link from one of the 30 supported services. One problem I saw was that short URL sites like xrl.in and others will keep popping up (I listed a site above that links 70 of these services). It’s going to take some work from the developer side to keep up with all of these new services. In addition, this doesn’t help with Twitter applications like ones that are Adobe Air based or developed using another type of framework. However, it looks like the developer is working on it and he is trying to get other applications to integrate to his API. Either way, check out this great extension and follow the developer on Twitter to get news on improvements. I look forward to see how this type of extension will evolve.
Short URL’s won’t be going anywhere soon…lets hope social media applications and end users start using them with a little bit security in mind.
What solutions do you think could solve the short URL problem?