Gaming services, hosting companies hit with new type of DDoS attack

Level 3 is warning it has seen a sudden spike in DDoS attacks using portmap

Gaming and hosting companies have been hit with a new kind of DDoS attack that could snowball without preventive steps, Level 3 Communications warned on Monday.

Attackers have figured out how to abuse portmap services that have been left openly accessible on the Internet, said Dale Drew, chief security officer for Level 3.

"We think it has the potential to be very, very bad," Drew said.

Portmap, also referred to as RPCbind, is an open-source utility for Unix systems but also is in Windows. It maps network port numbers to available services.

For example, portmap might be used if someone wants to mount a Windows drive from a Unix file system. Portmap would tell Unix where the drive is located and the right port number.

The problem is that many organizations have left portmap openly running on the Internet, allowing attackers to contact it, Drew said.

If portmap is queried, it can in some cases respond with a very large amount of data. Drew said the attackers are contacting open portmap servers, asking queries but then directing the responses to victim organizations. The UDP traffic overwhelms their networks, Drew said.

The method is referred to as a DDoS amplification attack. Depending on the query sent to portmap, the utility will send between seven to 27 times the traffic back -- or to a victim.

In December, attackers conducted devastating DDoS amplification attacks using remote code vulnerabilities in the network time protocol (NTP), which synchronizes clocks across computers.

The NTP DDoS attacks were some of the largest ever seen, Drew said. He thinks the portmap situation could rival the NTP problem, which is why Level 3 decided to go public with its findings.

About 1 million machines are running portmap open to the Internet, Level 3 found.

"We were very surprised to see how many Unix machines were running this [portmap] on the public Internet," Drew said.

The fix, Drew said, is easy: the portmap protocol should be filtered to be protected from the public Internet.

In the last few weeks, Level 3 has been watching the attackers refine their methods. The largest attacks occurred between Aug. 10 and 12, according to a blog post from Level 3.

Level 3 has a list of all the open portmap servers and has contacted its own customers that are running portmap. It has also sent the list to some ISPs so they can notify their customers to fix portmap.

Drew said he has an idea where the attackers are based, but Level 3 doesn't release attribution information since it may impact its ability to track them.

"We are watching how the bad guys react to that and if they evolve and change and modify," he said.

Join the newsletter!

Error: Please check your email address.
Rocket to Success - Your 10 Tips for Smarter ERP System Selection

Tags hosting companiesDDoS attacksecuritygaming servicesLevel 3 Communications

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

Jeremy Kirk

IDG News Service
Show Comments

Most Popular Reviews

Latest Articles

Resources

PCW Evaluation Team

Ben Ramsden

Sharp PN-40TC1 Huddle Board

Brainstorming, innovation, problem solving, and negotiation have all become much more productive and valuable if people can easily collaborate in real time with minimal friction.

Sarah Ieroianni

Brother QL-820NWB Professional Label Printer

The print quality also does not disappoint, it’s clear, bold, doesn’t smudge and the text is perfectly sized.

Ratchada Dunn

Sharp PN-40TC1 Huddle Board

The Huddle Board’s built in program; Sharp Touch Viewing software allows us to easily manipulate and edit our documents (jpegs and PDFs) all at the same time on the dashboard.

George Khoury

Sharp PN-40TC1 Huddle Board

The biggest perks for me would be that it comes with easy to use and comprehensive programs that make the collaboration process a whole lot more intuitive and organic

David Coyle

Brother PocketJet PJ-773 A4 Portable Thermal Printer

I rate the printer as a 5 out of 5 stars as it has been able to fit seamlessly into my busy and mobile lifestyle.

Kurt Hegetschweiler

Brother PocketJet PJ-773 A4 Portable Thermal Printer

It’s perfect for mobile workers. Just take it out — it’s small enough to sit anywhere — turn it on, load a sheet of paper, and start printing.

Featured Content

Latest Jobs

Don’t have an account? Sign up here

Don't have an account? Sign up now

Forgot password?