Hackers exploit Ruby on Rails vulnerability to compromise servers, create botnet

The targeted vulnerability was patched in January, but many servers haven't been updated yet

Hackers are actively exploiting a critical vulnerability in the Ruby on Rails Web application development framework in order to compromise Web servers and create a botnet.

The Ruby on Rails development team released a security patch for the vulnerability, which is known as CVE-2013-0156, back in January. However, some server administrators haven't yet updated their Rails installations.

Ruby on Rails is a popular framework for developing Web applications based on the Ruby programming language and is used by websites including Hulu, GroupOn, GitHub and Scribd.

"It's pretty surprising that it's taken this long [for an exploit] to surface in the wild, but less surprising that people are still running vulnerable installations of Rails," said Jeff Jarmoc, a security consultant with security research firm Matasano Security, Tuesday in a blog post.

The exploit that's currently being used by attackers adds a custom cron job -- a scheduled task on Linux machines -- that executes a sequence of commands.

Those commands download a malicious C source file from a remote server, compile it locally and execute it. The resulting malware is a bot that connects to an IRC (Internet Relay Chat) server and joins a predefined channel where it waits for commands from the attackers.

A precompiled version of the malware is also downloaded in case the compilation procedure fails on the compromised systems.

"Functionality is limited, but includes the ability to download and execute files as commanded, as well as changing servers," Jarmoc said. "There's no authentication performed, so an enterprising individual could hijack these bots fairly easily by joining the IRC server and issuing the appropriate commands."

Reports of malicious activity using this exploit were posted in recent days on several discussion boards and it also appears that some Web hosting providers were affected, Jarmoc said.

Users should update the Ruby on Rails installations on their servers to at least versions 3.2.11, 3.1.10, 3.0.19 or 2.3.15 which contain the patch for this vulnerability. However, the best course of action is probably to update to the latest available Rails versions, depending on the branch used, since other critical vulnerabilities have been addressed since then.

Attackers are increasingly compromising Web servers to use them as part of botnets. For example, many Apache servers have recently been infected with a piece of malware called Linux/Cdorked and versions of this malware were also developed for Lighttpd and Nginx Web servers.

Join the PC World newsletter!

Error: Please check your email address.

Tags intrusionsecurityMatasano SecuritysoftwareWeb serversExploits / vulnerabilities

Our Back to Business guide highlights the best products for you to boost your productivity at home, on the road, at the office, or in the classroom.

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

Lucian Constantin

IDG News Service
Show Comments

Essentials

Lexar® JumpDrive® S57 USB 3.0 flash drive

Learn more >

Microsoft L5V-00027 Sculpt Ergonomic Keyboard Desktop

Learn more >

Mobile

Lexar® JumpDrive® S45 USB 3.0 flash drive 

Learn more >

Exec

Lexar® JumpDrive® C20c USB Type-C flash drive 

Learn more >

Lexar® Professional 1800x microSDHC™/microSDXC™ UHS-II cards 

Learn more >

Audio-Technica ATH-ANC70 Noise Cancelling Headphones

Learn more >

HD Pan/Tilt Wi-Fi Camera with Night Vision NC450

Learn more >

Budget

Back To Business Guide

Click for more ›

Most Popular Reviews

Latest News Articles

Resources

PCW Evaluation Team

Azadeh Williams

HP OfficeJet Pro 8730

A smarter way to print for busy small business owners, combining speedy printing with scanning and copying, making it easier to produce high quality documents and images at a touch of a button.

Andrew Grant

HP OfficeJet Pro 8730

I've had a multifunction printer in the office going on 10 years now. It was a neat bit of kit back in the day -- print, copy, scan, fax -- when printing over WiFi felt a bit like magic. It’s seen better days though and an upgrade’s well overdue. This HP OfficeJet Pro 8730 looks like it ticks all the same boxes: print, copy, scan, and fax. (Really? Does anyone fax anything any more? I guess it's good to know the facility’s there, just in case.) Printing over WiFi is more-or- less standard these days.

Ed Dawson

HP OfficeJet Pro 8730

As a freelance writer who is always on the go, I like my technology to be both efficient and effective so I can do my job well. The HP OfficeJet Pro 8730 Inkjet Printer ticks all the boxes in terms of form factor, performance and user interface.

Michael Hargreaves

Windows 10 for Business / Dell XPS 13

I’d happily recommend this touchscreen laptop and Windows 10 as a great way to get serious work done at a desk or on the road.

Aysha Strobbe

Windows 10 / HP Spectre x360

Ultimately, I think the Windows 10 environment is excellent for me as it caters for so many different uses. The inclusion of the Xbox app is also great for when you need some downtime too!

Mark Escubio

Windows 10 / Lenovo Yoga 910

For me, the Xbox Play Anywhere is a great new feature as it allows you to play your current Xbox games with higher resolutions and better graphics without forking out extra cash for another copy. Although available titles are still scarce, but I’m sure it will grow in time.

Featured Content

Latest Jobs

Don’t have an account? Sign up here

Don't have an account? Sign up now

Forgot password?