Linux distributor Suse has warned of one of the most serious security holes to date in Version 2.6 of the Linux kernel, which could allow attackers to shut down a system running 2.6-based software.
The 2.6 kernel, completed at the end of last year, brings a number of enterprise-friendly features to Linux, but is still in the early stages of rolling out in commercial products. While a number of Linux vendors have released software for technical enthusiasts running the new kernel, Suse, which is owned by Novell Inc., is one of the few offering an enterprise product based on 2.6.
Red Hat Inc., for example, has backported many of the more important 2.6 features to the 2.4 kernel for use in Red Hat Enterprise Linux (RHEL), arguing that the older kernel is more stable. MandrakeSoft SA has introduced 2.6 into enthusiast, but not enterprise offerings. Suse claimed to be the first to introduce 2.6 into a retail Linux operating system in the spring of this year with Suse Linux 9.1.
The problem lies in the way the kernel handles iptables firewall logging, and only affects systems with iptables-based firewalls, such as SUSEfirewall2, Suse said. An attacker could use a malformed packet to shut down the system, according to Suse's advisory, which ranked the bug nine out of 10 in severity.
As an alternative to updating the kernel, users can disable firewall logging of IP and TCP options, but this isn't recommended. Suse said. Products running the older 2.4 kernel -- including the enterprise server products from Red Hat and MandrakeSoft -- aren't affected.
The bug affects Suse Linux 9.1 and Suse Linux Enterprise Server (SLES) 9; Suse Linux 9.2 isn't affected because the version of the kernel it uses, 2.6.8, already contains a fix.
At the same time, Suse patched a less serious flaw that could have allowed a user to gain root privileges; this bug only affects SLES 9 on the S/390 platform.
In an advisory, Danish security firm Secunia gave the denial-of-service flaw only a moderately critical rating, because it does not allow attackers to compromise a system. This is only the second bug in 2.6 that has merited such a rating; the first was a denial-of-service bug publicized in July.
Get the independent advice and expertise you need to support a virtual workforce.
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 »
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 »
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 »
1 Recommendation
