Microsoft Sends a Message After Bamital Messes with Bing
In the last three years, Microsoft has been involved in six botnet takedowns. This one, though, seems more personal.
- By Scott Bekker
- March 06, 2013
On Feb. 6, the Microsoft Digital Crimes Unit and U.S Marshals raided Web hosting companies in Virginia and New Jersey. Their aim was to shut down a multinational botnet used primarily to defraud online advertisers.
The latest chapter in the global game of whack-a-mole between computer megavendors and law enforcement against online criminals goes by the name Bamital.
Most botnets share a multifaceted structure. First, they must find a way to infect hundreds or thousands of client computers. Once those clients are infected, they serve as robots at the mercy of whatever instructions they receive from command-and-control servers. Botnets are commonly used to launch distributed denial-of-service (DDOS) attacks and spam campaigns.
Bamital's infection vector was a combination of drive-by downloads, usually on porn sites, and malware in peer-to-peer networks. According to Microsoft, multiple thousands of computers were caught up in the Bamital botnet. Although there was some evidence of use of the botnet for identity theft and DDOS attacks, the victim computers were primarily click-bots, which are used to generate bogus Web site visits for click-fraud schemes.
In some cases, infected users' searches on Google, Bing or Yahoo! would be redirected to a Bamital server, which would return results that pointed those users to sites of the control server's choosing. In other cases, users' browsers would visit targeted advertising sites without any user action or awareness.
That "bad traffic" was "bought and sold in a complex ecosystem of brokers and traffic trading," according to a Microsoft lawsuit filed in the U.S. District Court for the Eastern District of Virginia.
"Simply put, the ad owner paid for Internet traffic that is of no use," Microsoft wrote in a section of the lawsuit seeking damages from a number of John and Jane Does in the Russian Federation, Romania, South Korea, England and the United States. "There is a substantial risk that advertisers may attribute this problem to Microsoft and associate these problems with Microsoft's Bing and Bing Ads products, thereby diluting and tarnishing the value of these trademarks and brands."
Symantec has been tracking the Bamital botnet since 2009. The security company got its biggest break in understanding this particular botnet in 2011, when Spanish authorities allowed the company to analyze an instance of the botnet's command-and-control server hosted in Spain.
Symantec approached Microsoft for help to fight the botnet, which Symantec estimated as taking in $1.1 million a year or more based on observations of server usage and bidding activity in black-market traffic-broker sites.
In the last three years, Microsoft has been involved in six botnet takedowns to defend the overall security of the Web for Windows users. This one, though, seems more personal for Microsoft. The message of the raid: Don't mess with Bing.
More Columns by Scott Bekker:
Scott Bekker is editor in chief of Redmond Channel Partner magazine.