Updated kernel packages that fix a privilege escalation security issue in
the CentOS Linux 4 kernel are now available.
This security advisory has been rated as having important security impact
by the CentOS Security Response Team.
The Linux kernel handles the basic functions of the operating system.
During security research, CentOS discovered a behavioral flaw in core dump
handling. A local user could create a program that would cause a core file
to be dumped into a directory they would not normally have permissions to
write to. This could lead to a denial of service (disk consumption), or
allow the local user to gain root privileges. (CVE-2006-2451)
Prior to applying this update, users can remove the ability to escalate
privileges using this flaw by configuring core files to dump to an absolute
location. By default, core files are created in the working directory of
the faulting application, but this can be overridden by specifying an
absolute location for core files in /proc/sys/kernel/core_pattern. To
avoid a potential denial of service, a separate partition for the core
files should be used.
All CentOS Linux 4 users are advised to upgrade their kernels
to the packages associated with their machine architectures and
configurations as listed in this erratum.