Several security issues were fixed in the kernel.
It was discovered that the Stream Control Transmission Protocol (SCTP) implementation incorrectly calculated lengths. If the net.sctp.addip_enable variable was turned on, a remote attacker could send specially crafted traffic to crash the system. (CVE-2011-1573)
25 October 2011
A security issue affects these releases of Ubuntu and its derivatives:
Several security issues were fixed in the kernel.
It was discovered that the Stream Control Transmission Protocol (SCTP) implementation incorrectly calculated lengths. If the net.sctp.addip_enable variable was turned on, a remote attacker could send specially crafted traffic to crash the system. (CVE-2011-1573)
Ryan Sweat discovered that the kernel incorrectly handled certain VLAN packets. On some systems, a remote attacker could send specially crafted traffic to crash the system, leading to a denial of service. (CVE-2011-1576)
Timo Warns discovered that the EFI GUID partition table was not correctly parsed. A physically local attacker that could insert mountable devices could exploit this to crash the system or possibly gain root privileges. (CVE-2011-1776)
Dan Rosenberg discovered that the IPv4 diagnostic routines did not correctly validate certain requests. A local attacker could exploit this to consume CPU resources, leading to a denial of service. (CVE-2011-2213)
Vasiliy Kulikov discovered that taskstats did not enforce access restrictions. A local attacker could exploit this to read certain information, leading to a loss of privacy. (CVE-2011-2494)
Vasiliy Kulikov discovered that /proc/PID/io did not enforce access restrictions. A local attacker could exploit this to read certain information, leading to a loss of privacy. (CVE-2011-2495)
Robert Swiecki discovered that mapping extensions were incorrectly handled. A local attacker could exploit this to crash the system, leading to a denial of service. (CVE-2011-2496)
Dan Rosenberg discovered that the Bluetooth stack incorrectly handled certain L2CAP requests. If a system was using Bluetooth, a remote attacker could send specially crafted traffic to crash the system or gain root privileges. (CVE-2011-2497)
It was discovered that the wireless stack incorrectly verified SSID lengths. A local attacker could exploit this to cause a denial of service or gain root privileges. (CVE-2011-2517)
Ben Pfaff discovered that Classless Queuing Disciplines (qdiscs) were being incorrectly handled. A local attacker could exploit this to crash the system, leading to a denial of service. (CVE-2011-2525)
It was discovered that the EXT4 filesystem contained multiple off-by-one flaws. A local attacker could exploit this to crash the system, leading to a denial of service. (CVE-2011-2695)
Herbert Xu discovered that certain fields were incorrectly handled when Generic Receive Offload (CVE-2011-2723)
Christian Ohm discovered that the perf command looks for configuration files in the current directory. If a privileged user were tricked into running perf in a directory containing a malicious configuration file, an attacker could run arbitrary commands and possibly gain privileges. (CVE-2011-2905)
Vasiliy Kulikov discovered that the Comedi driver did not correctly clear memory. A local attacker could exploit this to read kernel stack memory, leading to a loss of privacy. (CVE-2011-2909)
Time Warns discovered that long symlinks were incorrectly handled on Be filesystems. A local attacker could exploit this with a malformed Be filesystem and crash the system, leading to a denial of service. (CVE-2011-2928)
Dan Kaminsky discovered that the kernel incorrectly handled random sequence number generation. An attacker could use this flaw to possibly predict sequence numbers and inject packets. (CVE-2011-3188)
Darren Lavender discovered that the CIFS client incorrectly handled certain large values. A remote attacker with a malicious server could exploit this to crash the system or possibly execute arbitrary code as the root user. (CVE-2011-3191)
Yogesh Sharma discovered that CIFS did not correctly handle UNCs that had no prefixpaths. A local attacker with access to a CIFS partition could exploit this to crash the system, leading to a denial of service. (CVE-2011-3363)
Gideon Naim discovered a flaw in the Linux kernel’s handling VLAN 0 frames. An attacker on the local network could exploit this flaw to cause a denial of service. (CVE-2011-3593)
The problem can be corrected by updating your system to the following package versions:
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.
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.