April 19, 2006

Linux kernel patch 'fixes' cross-platform bug

Linus Torvalds said there are a couple of reasons why his fix doesn't really help the bad guys. First, he disputed the idea that Virus.Linux.Bi is actually a virus

The hacker who created a widely reported cross-platform virus that could affect both Windows and Linux PCs may have inadvertently done some free bug testing for the Linux operating system.  

Linux creator Linus Torvalds said on Wednesday he had patched his operating system kernel to fix a bug that had been preventing the virus from running.

The virus, called Virus.Linux.Bi.a/ Virus.Win32.Bi.a, was first reported by security vendor Kaspersky Lab Ltd. on April 7, which labeled it an interesting proof of concept program, because of its ability to affect both Windows and Linux.

After discovering the virus did not work on recent versions of Linux, open-source developers did a little investigative work and discovered that this was due to an obscure bug in the compiler used by Linux. News of this bug was first reported on the NewsForge.com Web site.

The bug affects versions of Linux that were compiled using a certain kernel option, called REGPARM, which was recently enabled by default, according to Torvalds.

Torvalds has now patched the problem in his version of the Linux kernel, which is used by developers. Most users, however, won't see the patch until version 2.6.17 of the kernel is released, he said.

This patch fixes what Torvalds calls a "benign" bug that has no effect on most programs. It also helps Virus.Linux.bi work in systems where it otherwise would have been ineffective.

But Torvalds said there are a couple of reasons why his fix doesn't really help the bad guys. First, he disputed the idea that Virus.Linux.Bi is actually a virus. "It ends up really being just a program that writes to files that it has permissions to write to. Nothing wrong with that," he said. "It just does so in an interesting manner that means that it gathers more publicity."

And even if the proof of concept code could be put to malicious use, it would have been a trivial matter for "any serious bad guy" to overcome the compiler bug that was preventing it from working, Torvalds added.

"Fixing the bug in no way made for worse security," he said. "Quite the reverse: fixing a latent bug that doesn't matter today is absolutely required for good security tomorrow. Anybody who tells you otherwise is incompetent."

To date, Kaspersky has not seen any hackers adopt the proof of concept code for use in real attacks, though the security vendor says that it's still possible that malicious "black hat" hackers could put it to use. "There are always black-hatters out there that are going to try to use part of it to create something new," said Shane Coursen a senior technical consultant with the company. "We may see another virus using the same method of cross-platform infection."

Close

On Twitter now

Security

Powered by Twitter

On Twitter now

additional resources
White Paper - How to Improve Delivery of Advanced Web Applications

White Paper

Virtual Workforce: The Key to Expanding The Business While Cutting Costs

Get the independent advice and expertise you need to support a virtual workforce.

Go inside:
The three-step approach to making a virtual workforce a reality.
The four flavors of client virtualization technologies.
The three key initiatives that solve IT challenges.
Download now »
White Paper: Successfully Secure Your Wireless LAN With Wi-Fi firewalls.

White Paper

Addressing Linux Threats Leveraging Fewer Resources

The increase in Linux popularity has increased the frequency and sophistication of malware attacks. Read this 2 page white paper now to learn how you can protect your Linux environment with real-time protection that is certified by all major Linux vendors.

Download now »
White Paper - The 2009 Handbook of Application Delivery

White Paper

The 2009 Handbook of Application Delivery

Ensuring acceptable application delivery will become even more difficult over the next few years. As a result, IT organizations need to ensure that the approach that they take to resolving the current application delivery challenges can scale to support the emerging challenges. This handbook elaborates on the key tasks associated with planning, optimization, management and control and provides decision criteria to help IT organizations choose appropriate solutions.

Download now »
White Paper - Is Your Backup System Outdated?

White Paper

Mid-range Storage Considerations

A common misconception is that mid-range storage requirements are dramatically different than that of a larger enterprise. Mid-range storage users may require less capacity, but they have similar functionality and management requirements. This ESG paper examines mid-range storage needs and reviews a new solution that adjusts size while retaining value, performance and functionality.

Download now »

Sign up to receive Security Resource Alerts

Subscribe to the Security Central Newsletter

Stay informed of the latest security threats and fixes.

White paper

Log Management: How to Develop the Right Strategy for Business and Compliance

This white paper provides guidance on how to develop a strategic approach to managing and monitoring logs, a key function required for compliance with many regulatory mandates and a critical defense against security threats.

Download now! »

White paper

The Essential Series: Security Information Management

Learn about the processes and technologies that support security information management (SIM) operations, as well as the business case for SIM. The series examines different options for implementing SIM and gives you evaluation criteria for selecting the best option for your organization.

Download now! »

White paper

Aberdeen: Choosing and Consuming Managed Security Services

Learn the strategies, actions, and capabilities that Best-in-Class organizations employ and technologies they choose to obtain superior performance against various security performance metrics. This report provides guidelines for identifying which security solutions to consume as a MSS and defines best practices for choosing and managing MSSPs.

Download now! »
©1994-2010 Infoworld, Inc.