
Computerworld is New Zealand's only specialised information systems fortnightly.
Subscribe now for $97.50 (24 issues) and save more than 37% off the cover price!
 Get the latest news from Computerworld delivered via email.
Sign up now
 Subscribe to Computerworld's
RSS newsfeed here and get news stories as they break.
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, is one of the few offering an enterprise product based on 2.6.
Red Hat, for example, has backported many of the more important 2.6 features to the 2.4 kernel for use in Red Hat Enterprise Linux, 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 ith the release earlier this year of 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 says. An attacker could use a malformed packet to shut down the system, according to Suse's advisory, which ranks the bug nine out of ten 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 says. 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 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 SUSE Linux Enterprise Server 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 publicised in July.
|