High Nessus Plugin ID 13836
SynopsisThe remote host is missing a vendor-supplied security patch
DescriptionThe remote host is missing the patch for the advisory SUSE-SA:2004:020 (kernel).
Multiple security vulnerabilities are being addressed with this security update of the Linux kernel.
Kernel memory access vulnerabilities are fixed in the e1000, decnet, acpi_asus, alsa, airo/WLAN, pss and mpu401 drivers. These vulnerabilities can lead to kernel memory read access, write access and local denial of service conditions, resulting in access to the root account for an attacker with a local account on the affected system.
Missing Discretionary Access Control (DAC) checks in the chown(2) system call allow an attacker with a local account to change the group ownership of arbitrary files, which leads to root privileges on affected systems. It is specific to kernel version 2.6 based systems such as the SUSE Linux 9.1 product, that only local shell access is needed to exploit this vulnerability. An interesting variant of the missing checks is that the ownership of files in the /proc filesystem can be altered, while the changed ownership still does not allow the files to be accessed as a non-root user for to be able to exploit the vulnerability. Systems that are based on a version 2.4 kernel are not vulnerable to the /proc weakness, and exploitation of the weakness requires the use of the kernel NFS server (knfsd). If the knfsd NFS server is not activated (it is off by default), the vulnerability is not exposed. These issues related to the chown(2) system call have been discovered by Michael Schroeder and Ruediger Oertel, both SUSE LINUX.
The only network-related vulnerability fixed with the kernel updates that are subject to this announcement affect the SUSE Linux 9.1 distribution only, as it is based on a 2.6 kernel. Found and reported to bugtraq by Adam Osuchowski and Tomasz Dubinski, the vulnerability allows a remote attacker to send a specially crafted TCP packet to a vulnerable system, causing that system to stall if it makes use of TCP option matching netfilter rules.
In some rare configurations of the SUSE Linux 9.1 distribution, some users have experienced stalling systems during system startup. These problems are fixed with this kernel update.