Uočeni su i ispravljeni višestruki propusti jezgre operacijskog sustava Ubuntu 12.04 LTS koje je lokalni napadač mogao iskoristiti za dobivanje većih privilegija te izvođenje napada uskraćivanjem usluge (eng. Denial of Service attack).

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Ubuntu Security Notice USN-1473-1
June 13, 2012

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

- Ubuntu 12.04 LTS

Summary:

Several security issues were fixed in the kernel.

Software Description:
- linux: Linux kernel

Details:

A flaw was discovered in the Linux kernel's KVM (kernel virtual machine).
An administrative user in the guest OS could leverage this flaw to cause a
denial of service in the host OS. (CVE-2012-2121)

Schacher Raindel discovered a flaw in the Linux kernel's memory handling
when hugetlb is enabled. An unprivileged local attacker could exploit this
flaw to cause a denial of service and potentially gain higher privileges.
(CVE-2012-2133)

Stephan Mueller reported a flaw in the Linux kernel's dl2k network driver's
handling of ioctls. An unprivileged local user could leverage this flaw to
cause a denial of service. (CVE-2012-2313)

Timo Warns reported multiple flaws in the Linux kernel's hfsplus
filesystem. An unprivileged local user could exploit these flaws to gain
root system priviliges. (CVE-2012-2319)

Xi Wang discovered a flaw in the Linux kernel's i915 graphics driver
handling of cliprect on 32 bit systems. An unprivileged local attacker
could leverage this flaw to cause a denial of service or potentially gain
root privileges. (CVE-2012-2383)

Xi Wang discovered a flaw in the Linux kernel's i915 graphics driver
handling of buffer_count on 32 bit systems. An unprivileged local attacker
could leverage this flaw to cause a denial of service or potentially gain
root privileges. (CVE-2012-2384)

Update instructions:

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

Ubuntu 12.04 LTS:
  linux-image-3.2.0-25-generic    3.2.0-25.40
  linux-image-3.2.0-25-generic-pae  3.2.0-25.40
  linux-image-3.2.0-25-highbank   3.2.0-25.40
  linux-image-3.2.0-25-omap       3.2.0-25.40
  linux-image-3.2.0-25-powerpc-smp  3.2.0-25.40
  linux-image-3.2.0-25-powerpc64-smp  3.2.0-25.40
  linux-image-3.2.0-25-virtual    3.2.0-25.40

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

ATTENTION: Due to an unavoidable ABI change the kernel updates have
been given a new version number, which requires you to recompile and
reinstall all third party kernel modules you might have installed. If
you use linux-restricted-modules, you have to update that package as
well to get modules which work with the new kernel version. Unless you
manually uninstalled the standard kernel metapackages (e.g. linux-generic,
linux-server, linux-powerpc), a standard system upgrade will automatically
perform this as well.

References:
  http://www.ubuntu.com/usn/usn-1473-1
  CVE-2012-2121, CVE-2012-2133, CVE-2012-2313, CVE-2012-2319,
  CVE-2012-2383, CVE-2012-2384

Package Information:
  https://launchpad.net/ubuntu/+source/linux/3.2.0-25.40