U radu jezgre operacijskog sustava Ubuntu uočeno je nekoliko sigurnosnih propusta. Zlonamjerni ih korisnik može iskoristiti za izvođenje napada uskraćivanjem usluge (DoS).

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Ubuntu Security Notice USN-1193-1
August 19, 2011

linux vulnerabilities
==========================================================================

A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 11.04

Summary:

Multiple kernel flaws have been fixed.

Software Description:
- linux: Linux kernel

Details:

Timo Warns discovered that the GUID partition parsing routines did not
correctly validate certain structures. A local attacker with physical
access could plug in a specially crafted block device to crash the system,
leading to a denial of service. (CVE-2011-1577)

Phil Oester discovered that the network bonding system did not correctly
handle large queues. On some systems, a remote attacker could send
specially crafted traffic to crash the system, leading to a denial of
service. (CVE-2011-1581)

Vasiliy Kulikov discovered that taskstats listeners were not correctly
handled. A local attacker could expoit this to exhaust memory and CPU
resources, leading to a denial of service. (CVE-2011-2484)

Sami Liedes discovered that ext4 did not correctly handle missing root
inodes. A local attacker could trigger the mount of a specially crafted
filesystem to cause the system to crash, leading to a denial of service.
(CVE-2011-2493)

Update instructions:

The problem can be corrected by updating your system to the following
package versions:

Ubuntu 11.04:
  linux-image-2.6.38-11-generic   2.6.38-11.48
  linux-image-2.6.38-11-generic-pae  2.6.38-11.48
  linux-image-2.6.38-11-omap      2.6.38-11.48
  linux-image-2.6.38-11-powerpc   2.6.38-11.48
  linux-image-2.6.38-11-powerpc-smp  2.6.38-11.48
  linux-image-2.6.38-11-powerpc64-smp  2.6.38-11.48
  linux-image-2.6.38-11-server    2.6.38-11.48
  linux-image-2.6.38-11-versatile  2.6.38-11.48
  linux-image-2.6.38-11-virtual   2.6.38-11.48

After a standard system update you need to reboot your computer to make
all the necessary changes.

References:
  http://www.ubuntu.com/usn/usn-1193-1
  CVE-2011-1577, CVE-2011-1581, CVE-2011-2484, CVE-2011-2493

Package Information:
  https://launchpad.net/ubuntu/+source/linux/2.6.38-11.48