RHSA-2009:0427 - Security Advisory

Topic

Updated udev packages that fix one security issue are now available for Red
Hat Enterprise Linux 5.

This update has been rated as having important security impact by the Red
Hat Security Response Team.

Description

udev provides a user-space API and implements a dynamic device directory,
providing only the devices present on the system. udev replaces devfs in
order to provide greater hot plug functionality. Netlink is a datagram
oriented service, used to transfer information between kernel modules and
user-space processes.

It was discovered that udev did not properly check the origin of Netlink
messages. A local attacker could use this flaw to gain root privileges via
a crafted Netlink message sent to udev, causing it to create a
world-writable block device file for an existing system block device (for
example, the root file system). (CVE-2009-1185)

Red Hat would like to thank Sebastian Krahmer of the SUSE Security Team for
responsibly reporting this flaw.

Users of udev are advised to upgrade to these updated packages, which
contain a backported patch to correct this issue. After installing the
update, the udevd daemon will be restarted automatically.

Solution

Before applying this update, make sure that all previously-released
errata relevant to your system have been applied.

This update is available via Red Hat Network. Details on how to use
the Red Hat Network to apply this update are available at
http://kbase.redhat.com/faq/docs/DOC-11259

Affected Products

• Red Hat Enterprise Linux Server 5 x86_64
• Red Hat Enterprise Linux Server 5 ia64
• Red Hat Enterprise Linux Server 5 i386
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 5.3 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 5.3 ia64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 5.3 i386
• Red Hat Enterprise Linux Workstation 5 x86_64
• Red Hat Enterprise Linux Workstation 5 i386
• Red Hat Enterprise Linux Desktop 5 i386
• Red Hat Enterprise Linux for IBM z Systems 5 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 5.3 s390x
• Red Hat Enterprise Linux for Power, big endian 5 ppc
• Red Hat Enterprise Linux Server from RHUI 5 x86_64
• Red Hat Enterprise Linux Server from RHUI 5 i386
• Red Hat Enterprise Linux Server - AUS 5.3 x86_64
• Red Hat Enterprise Linux Server - AUS 5.3 ia64
• Red Hat Enterprise Linux Server - AUS 5.3 i386
• Red Hat Enterprise Linux Desktop 5 x86_64
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 5.3 ppc

Fixes

• BZ - 495051 - CVE-2009-1185 udev: Uncheck origin of NETLINK messages

CVEs

• CVE-2009-1185

References

• http://www.redhat.com/security/updates/classification/#important