Spanish police take down massive Mariposa botnet

The Mariposa botnet ran under the radar but was one of the biggest ever

Spanish authorities have arrested three men in an operation that has crushed a major botnet network of infected computers.

The Mariposa botnet, which appears to be one of the world's largest, took over millions of computers, many of which continue to be infected, security researchers said Tuesday.

An informal group of volunteers, calling itself the Mariposa Working Group, disabled Mariposa's command-and-control servers on Dec. 23 and handed over information about the criminals behind it to law enforcement in Spain and the U.S. Spain's Guardia Civil is expected to disclose more details of the arrests on Wednesday, during a morning press conference.

Mariposa-infected computers were linked to 13 million unique Internet Protocol addresses, said Pedro Bustamante, a researcher with Panda Security. It's hard to pinpoint the exact size of the botnet from that number, but it appears to be one of the world's largest. Researchers studying the notorious Conficker botnet have linked it to half as many IP addresses.

However, with the command-and-control servers in the working group's hands, the infected computers cannot be misused right now.

Researchers have spotted Mariposa infections in half of the Fortune 100, as well as hundreds of government agencies, said Chris Davis, CEO of Defense Intelligence, the company that first identified the botnet in May of last year. Defense Intelligence and Panda Security are part of the Mariposa Working Group, as are researchers at Georgia Tech.

The criminals used Mariposa for typical cyberscams: They stole banking credentials and launched distributed denial-of-service (DDoS) attacks. However, they did not use it to push fake antivirus products, a move that helped keep Mariposa under the radar. "The bot was itself very silent," Bustamante said.

One of those DDoS attacks was directed at Defense Intelligence's computers in Ottawa. Angered by the company's efforts to defeat them, the hackers sent data to the company's servers at the rate of 900M bits per second after they briefly regained control of the botnet on Jan. 25.

Antivirus companies did a good job of detecting some versions of the Mariposa code, but the bad guys changed their software often enough -- sometimes every 48 hours -- that many versions of the malware went undetected. "The AV companies couldn't write signatures fast enough," Davis said.

The researchers say that there are still many Mariposa-infected PCs out there, but they are working with antivirus vendors to improve detection and remove the malicious code from the Internet. Over the next month or two, there should be "a pretty big decline" in the number of infected computers, Davis said.

With the help of the Mariposa Working Group, Spanish police arrested the first Mariposa operator in January in Bilbao, Spain, Davis said. The other two men were arrested last week. He was not authorized to release the names of those arrested.

The criminals' fatal mistake was using a real name while registering command-and-control domains, Davis said. They apparently thought they would be anonymous because they used a private domain name registrar, but that company ended up cooperating with the Mariposa Working Group. "There are so many botnets and so many guys doing this," Davis said, "they get cocky; they get careless."

Spain's Guardia Civil could not be reached for comment, but the Associated Press quoted the Guardia Civil's Cesar Lorenza as saying that Mariposa was run by "normal people who are earning a lot of money with cybercrime," who built the botnet with the help of contacts in the criminal underworld.

The U.S. Federal Bureau of Investigation was involved in the action, but the FBI did not return calls seeking comment Tuesday.

News of the arrests first leaked out in the Spanish media on Monday, Davis said.

Join the newsletter!

Or

Sign up to gain exclusive access to email subscriptions, event invitations, competitions, giveaways, and much more.

Membership is free, and your security and privacy remain protected. View our privacy policy before signing up.

Error: Please check your email address.

Tags botnets

Keep up with the latest tech news, reviews and previews by subscribing to the Good Gear Guide newsletter.

Robert McMillan

IDG News Service
Show Comments

Cool Tech

Toys for Boys

Family Friendly

Stocking Stuffer

SmartLens - Clip on Phone Camera Lens Set of 3

Learn more >

Christmas Gift Guide

Click for more ›

Brand Post

Most Popular Reviews

Latest Articles

Resources

PCW Evaluation Team

Michael Hargreaves

Microsoft Office 365/Dell XPS 15 2-in-1

I’d recommend a Dell XPS 15 2-in-1 and the new Windows 10 to anyone who needs to get serious work done (before you kick back on your couch with your favourite Netflix show.)

Maryellen Rose George

Brother PT-P750W

It’s useful for office tasks as well as pragmatic labelling of equipment and storage – just don’t get too excited and label everything in sight!

Cathy Giles

Brother MFC-L8900CDW

The Brother MFC-L8900CDW is an absolute stand out. I struggle to fault it.

Luke Hill

MSI GT75 TITAN

I need power and lots of it. As a Front End Web developer anything less just won’t cut it which is why the MSI GT75 is an outstanding laptop for me. It’s a sleek and futuristic looking, high quality, beast that has a touch of sci-fi flare about it.

Emily Tyson

MSI GE63 Raider

If you’re looking to invest in your next work horse laptop for work or home use, you can’t go wrong with the MSI GE63.

Laura Johnston

MSI GS65 Stealth Thin

If you can afford the price tag, it is well worth the money. It out performs any other laptop I have tried for gaming, and the transportable design and incredible display also make it ideal for work.

Featured Content

Product Launch Showcase

Don’t have an account? Sign up here

Don't have an account? Sign up now

Forgot password?