The tool looks at every public post as it appears on Twitter, extracts any URLs in them and analyzes the Web page they lead to, expanding any URLS that have been shortened, Costin Raiu, a senior malware analyst at Kaspersky, said in an interview.
The company is scanning nearly 500,000 new unique URLs that appear in Twitter posts daily, he said. Of those, anywhere between 100 and 1,000 are malware attacks. Twitter has also been targeted by the Koobface virus which posts malicious links from infected users' accounts.
About 26 percent of the total posts contain URLs, and many of those lead to spam sites that are marketing products or services and aren't considered malware, according to Raiu. Tens of thousands of different accounts are posting spam links, most likely from accounts created by bots, he said. The most frequent URLs posted lead to online dating sites, he added.
For more, read "Kaspersky tool detects malware in Twitter links" on CNET News.