Ubuntu has issued an update for the kernel. This fixes multiple vulnerabilities, which can be exploited by malicious, local users to compromise a vulnerable system and by malicious people to cause a DoS (Denial of Service).

1) An error exists within Ext4 "move extents" ioctl, which can be exploited to overwrite arbitrary files on the system.

For more information:
SA37658

2) Due to an error within the "ip_defrag()" function in net/ipv4/ip_fragment.c a NULL pointer dereference can occur, which can potentially be exploited by sending overly large packets to a vulnerable system.

Solution
Apply updated packages.
Further details available to Secunia VIM customers

Provided and/or discovered by
1) Akira Fujita
2) David Ford

Original Advisory
USN-869-1:
http://www.ubuntu.com/usn/USN-869-1

Other references
Further details available to Secunia VIM customers

Deep Links
Links available to Secunia VIM customers