Bugat Trojan linked to LinkedIn phishing campaign

Researchers have discovered a new version of the Bugat financial malware used to commit online fraud. Bugat was distributed in the recent phishing campaign targeting LinkedIn users, which was generally considered to be trying to infect machines with the more common Zeus Trojan.

The emergence of this new version of Bugat appears to be an attempt by criminals to diversify their attack tools using a platform that is less well known and therefore harder to detect and block.

Bugat is similar in functionality to its better known financial malware brethren Zeus, Clampi and Gozi. It targets Internet Explorer and Firefox browsers and harvests information during online banking sessions. The stolen financial credentials are used to commit fraudulent Automated Clearing House (ACH) and wire transfer transactions mostly against small to midsized businesses, which result in high-value losses. Bugat is three times more common in the US than Europe, but its distribution is still fairly low.

In last week’s attack, LinkedIn users received emails reminding them of pending messages in their account and providing a malicious URL. When a victim clicked on the link they were directed to a fraudulent website where a java applet fetched and installed the Bugat executable. LinkedIn spam email is an effective tool to push malware to enterprise users, and is being used to gather credentials for commercial bank accounts and other sensitive services used by businesses.

Trusteer warns that the recent industry focus on Zeus is making it easier for other Trojans, like Bugat, SpyEye, and Carberp which are less wide spread but equally sophisticated, to avoid detection. Carberp currently targets nine banks in the United States, Denmark, The Netherlands, Germany, and Israel. These lesser known financial malware platforms are expected to increasingly compete with the Zeus toolkit to become the new Trojan of choice for criminal groups.