Menu
RubyGems DNS flaw now patched after second try

RubyGems DNS flaw now patched after second try

Those using the distribution client are advised to patch immediately to version 2.4.8 or higher

RubyGem has released a second fix for a flaw that could be used to substitute a legitimate Ruby program with malware during downloading.

RubyGem has released a second fix for a flaw that could be used to substitute a legitimate Ruby program with malware during downloading.

A revised patch has been released for a flaw in the distribution platform for Ruby applications, RubyGems, which could be used to deliver malware to someone trying to download a program.

RubyGems lets people search for a "gem," which is a packaging format for Ruby applications and code libraries. Ruby developers publish a gem when an application is ready.

Security researchers from Trustwave found a problem with the platform. When people search for a gem, RubyGems uses a DNS (Domain Name System) SRV record request to find a server hosting a particular gem.

The request, however, "does not require that DNS replies come from the same security domain as the original gem source," according to a writeup, which Trustwave plans to release on its blog on Tuesday.

An attacker using the flaw could redirect a RubyGems client to download a gem from a different server and instead supply a malicious program, Trustwave wrote. It then bypasses any SSL/TLS check.

"We wrote a fully functional gem trojaning service that demonstrates how an attacker could simply trojan Ruby gems transparently over the wire while the user was installing them," Trustwave wrote.

Most gems aren't digitally signed, either, so there's no second check to ensure a program is what it purports to be. Some 1.2 million gems are installed a day, so there's a large potential group of victims, according to Trustwave, which also collaborated with OpenDNS to get insight on the number of DNS SRV requests for gems.

RubyGems issued a patch for the flaw in mid-May, but it was incomplete, wrote Jonathan Claudius, lead security researcher at Trustwave, in an email. The organization released a second patch on June 8. The fix validates the SRV record under the original domain, according to a RubyGems blog post.

Trustwave decided to hold off publishing information on the flaw until now to give people time to patch, Claudius said. "Users are slow to fix it," he wrote.

The flaw is CVE-2015-3900, and users should be running version 2.4.8 or greater of RubyGems. Versions between 2.0 and 2.4.6 are vulnerable.

Send news tips and comments to jeremy_kirk@idg.com. Follow me on Twitter: @jeremy_kirk


Follow Us

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 trustwaveExploits / vulnerabilities

Featured

Slideshows

Malwarebytes shoots the breeze with channel, prospects

Malwarebytes shoots the breeze with channel, prospects

A Kumeu, Auckland, winery was the venue for a Malwarebytes event for partner and prospect MSPs - with some straight shooting on the side. The half-day getaway, which featured an archery competition, lunch and wine-tasting aimed at bringing Malwarebytes' local New Zealand and top and prospective MSP partners together to celebrate recent local successes, and discuss the current state of malware in New Zealand. This was also a unique opportunity for local MSPs to learn about how they can get the most out of Malwarebytes' MSP program and offering, as more Kiwi businesses are targeted by malware.

Malwarebytes shoots the breeze with channel, prospects
EDGE 2019: Channel forges new partnerships during evening networking

EDGE 2019: Channel forges new partnerships during evening networking

Partners, vendors and distributors reconnected during a number of social gatherings during EDGE 2019. The first evening saw the channel congregate for a welcome party at the Hamilton Island yacht club, while the main poolside proved to be the perfect stop for a barbecue on the final night.

EDGE 2019: Channel forges new partnerships during evening networking
Show Comments