As Twitter has been getting more and more popular, it is increasingly targeted by worms, spam and account hijacking. Hackers make use of its popularity to post spam messages on hot topics in hopes of gaining clicks to malicious sites.

The 140 character limit imposed by Twitter often requires shortening the real URL. This also impose risk to the user, because people don’t know where they will be taken if they will click the link.

But now thing has changed. The development team at Twitter has now working on its security aspect and started to filter Tweets that contain links to known malware sites.

According to F-Secure weblog, Twitter makes use of Google Safe Browsing API for this; however, this new security feature has not been officially yet announced (via - F-Secure).