Ubuntu Security Notice USN-1336-1

23rd January, 2012

linux vulnerability

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

• Ubuntu 11.10

Summary

The system could be made to run programs as an administrator.

Software description

• linux - Linux kernel

Details

Clement Lecigne discovered a bug in the HFS filesystem. A local attacker
could exploit this to cause a kernel oops. (CVE-2011-2203)

A bug was discovered in the XFS filesystem's handling of pathnames. A local
attacker could exploit this to crash the system, leading to a denial of
service, or gain root privileges. (CVE-2011-4077)

A flaw was found in how the Linux kernel handles user-defined key types. An
unprivileged local user could exploit this to crash the system.
(CVE-2011-4110)

A flaw was found in the Journaling Block Device (JBD). A local attacker
able to mount ext3 or ext4 file systems could exploit this to crash the
system, leading to a denial of service. (CVE-2011-4132)

Clement Lecigne discovered a bug in the HFS file system bounds checking.
When a malformed HFS file system is mounted a local user could crash the
system or gain root privileges. (CVE-2011-4330)

Chen Haogang discovered an integer overflow that could result in memory
corruption. A local unprivileged user could use this to crash the system.
(CVE-2012-0044)

Jüri Aedla discovered that the kernel incorrectly handled /proc/<pid>/mem
permissions. A local attacker could exploit this and gain root privileges.
(CVE-2012-0056)

Update instructions

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

Ubuntu 11.10:

linux-image-3.0.0-15-omap 3.0.0-15.26

linux-image-3.0.0-15-generic 3.0.0-15.26

linux-image-3.0.0-15-powerpc-smp 3.0.0-15.26

linux-image-3.0.0-15-server 3.0.0-15.26

linux-image-3.0.0-15-generic-pae 3.0.0-15.26

linux-image-3.0.0-15-powerpc64-smp 3.0.0-15.26

linux-image-3.0.0-15-powerpc 3.0.0-15.26

linux-image-3.0.0-15-virtual 3.0.0-15.26

To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.

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

References

CVE-2011-2203, CVE-2011-4077, CVE-2011-4110, CVE-2011-4132, CVE-2011-4330, CVE-2012-0044, CVE-2012-0056