USN-1239-1: Linux kernel (EC2) vulnerabilities
25 October 2011
A security issue affects these releases of Ubuntu and its derivatives:
- Ubuntu 10.04 LTS
Several security issues were fixed in the kernel.
- linux-ec2 - Linux kernel for EC2
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)
Vasiliy Kulikov and Dan Rosenberg discovered that ecryptfs did not correctly check the origin of mount points. A local attacker could exploit this to trick the system into unmounting arbitrary mount points, leading to a denial of service. (CVE-2011-1833)
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)
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 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)
Fernando Gont discovered that the IPv6 stack used predictable fragment identification numbers. A remote attacker could exploit this to exhaust network resources, leading to a denial of service. (CVE-2011-2699)
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)
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)
Han-Wen Nienhuys reported a flaw in the FUSE kernel module. A local user who can mount a FUSE file system could cause a denial of service. (CVE-2011-3353)
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.