Researchers caution against TCP/IP weakness

After keeping the flaw quiet for years, the researchers hope that going public will help accelerate the creation of a solution.

Researchers at Finnish security firm Outpost 24 claim to have discovered a flaw in the Internet Protocol that can disrupt any computer or server. After keeping the flaw quiet for years, the researchers hope that going public will help accelerate the creation of a solution.

The flaw allows attackers to cripple computers and servers by sending a few specially formed TCP/IP packets. The result can be compared to a denial of service attack, in which networks are flooded with traffic. But in the case of the newly revealed flaw, only a minimum of traffic is required. "We're talking 10 packets per second to take down one service," Jack Lewis, a senior researcher with Outpost24 told Webwereld, an IDG affiliate.

Researchers at Fox-IT, a Dutch security firm, confirm the issue. "Based on the available information, this vulnerability may be a serious problem for system availability," observed Erwin Paternotte, a researcher with Fox-IT. "If the technical details are publicly disclosed, performing a denial-of-service attack will become relatively trivial."

The problem surfaced during a test scan of 67 million Internet hosts. The researchers were alerted when a test caused some hosts to become unresponsive. Further investigation led to an issue in the TCP/IP stack. After a connection is successfully made, important system resources are at the attacker's disposal.

Each operating system is affected by the flaw, although different systems respond in different ways. "Each operating system does behave differently, of course. You might notice with OS X that a couple attacks that don't seem to bother too much completely devastate Windows XP and the other way around," said Lewis.

The researchers have crafted proof-of-concept code that demonstrates the issues. They claim that they haven't seen a single implementation of TCP/IP that wasn't vulnerable. Systems furthermore will remain unresponsive after an attack. "After the attack is over, the system never seems to recover until it is rebooted," said Robert Lee, Outpost24's chief security officer.

Firewalls or intrusion prevention systems are unable to mitigate the flaw, because they too support TCP/IP and are therefore a potential attack target.

The researchers so far have conceived five different attack scenarios, but they argue that as many as 30 would feasible. "You basically have to sit there and stare through code and figure out what stages you can get to," Lewis said.

The researchers are publicizing their finding after keeping quiet for three years, although they don't plan to fully disclose all the flaw's details. "We hope we can raise awareness and get more people that are smarter than us involved in looking for a solution," Lee said. Just because we can't think of a solution doesn't mean there isn't one, just that we haven't thought of it yet."

But there is another reason. Lee and Lewis see the migration toward IPv6 as a risk that could aggravate the situation. IPv6 "only makes the issue bigger, because the address space is bigger," Lee said.

The Finnish CERT is coordinating research into the security issue and education to software vendors affected by the flaw.

Lee and Lewis will present their findings on Oct. 17 at the T2 security conference in Helsinki.

A podcast interview in English with the researchers can be found on De Beveiligingsupdate.

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

Brenno de Winter

WebWereld Netherlands
Show Comments

Brand Post

Most Popular Reviews

Latest Articles

Resources

PCW Evaluation Team

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.

Andrew Teoh

Brother MFC-L9570CDW Multifunction Printer

Touch screen visibility and operation was great and easy to navigate. Each menu and sub-menu was in an understandable order and category

Louise Coady

Brother MFC-L9570CDW Multifunction Printer

The printer was convenient, produced clear and vibrant images and was very easy to use

Edwina Hargreaves

WD My Cloud Home

I would recommend this device for families and small businesses who want one safe place to store all their important digital content and a way to easily share it with friends, family, business partners, or customers.

Walid Mikhael

Brother QL-820NWB Professional Label Printer

It’s easy to set up, it’s compact and quiet when printing and to top if off, the print quality is excellent. This is hands down the best printer I’ve used for printing labels.

Featured Content

Product Launch Showcase

Latest Jobs

Don’t have an account? Sign up here

Don't have an account? Sign up now

Forgot password?