USN-416-1: Linux kernel vulnerabilities

10 February 2007

linux-source-2.6.122.6.152.6.17 vulnerabilities

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

  • Ubuntu 6.10
  • Ubuntu 6.06 LTS
  • Ubuntu 5.10

Software Description

Details

Mark Dowd discovered that the netfilter iptables module did not correcly handle fragmented IPv6 packets. By sending specially crafted packets, a remote attacker could exploit this to bypass firewall rules. This has has already been fixed for Ubuntu 6.10 in USN-395-1; this is the corresponding fix for Ubuntu 6.06.(CVE-2006-4572)

Doug Chapman discovered an improper lock handling in the mincore() function. A local attacker could exploit this to cause an eternal hang in the kernel, rendering the machine unusable. (CVE-2006-4814)

Al Viro reported that the ISDN PPP module did not initialize the reset state timer. By sending specially crafted ISDN packets, a remote attacker could exploit this to crash the kernel. (CVE-2006-5749)

Various syscalls (like listxattr()) misinterpreted the return value of return_EIO() when encountering bad inodes. By issuing particular system calls on a malformed file system, a local attacker could exploit this to crash the kernel. (CVE-2006-5753)

The task switching code did not save and restore EFLAGS of processes. By starting a specially crafted executable, a local attacker could exploit this to eventually crash many other running processes. This only affects the amd64 platform. (CVE-2006-5755)

A race condition was found in the grow_buffers() function. By mounting a specially crafted ISO9660 or NTFS file system, a local attacker could exploit this to trigger an infinite loop in the kernel, rendering the machine unusable. (CVE-2006-5757)

A buffer overread was found in the zlib_inflate() function. By tricking an user into mounting a specially crafted file system which uses zlib compression (such as cramfs), this could be exploited to crash the kernel. (CVE-2006-5823)

The ext3 file system driver did not properly handle corrupted data structures. By mounting a specially crafted ext3 file system, a local attacker could exploit this to crash the kernel. (CVE-2006-6053)

The ext2 file system driver did not properly handle corrupted data structures. By mounting a specially crafted ext2 file system, a local attacker could exploit this to crash the kernel. (CVE-2006-6054)

The hfs file system driver did not properly handle corrupted data structures. By mounting a specially crafted hfs file system, a local attacker could exploit this to crash the kernel. This only affects systems which enable SELinux (Ubuntu disables SELinux by default). (CVE-2006-6056)

Several vulnerabilities have been found in the GFS2 file system driver. Since this driver has never actually worked in Ubuntu 6.10, it has been disabled. This only affects Ubuntu 6.10. (CVE-2006-6057)

Marcel Holtman discovered several buffer overflows in the Bluetooth driver. By sending Bluetooth packets with specially crafted CAPI messages, a remote attacker could exploit these to crash the kernel. (CVE-2006-6106)

Update instructions

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

Ubuntu 6.10
linux-image-2.6.17-11-386 - 2.6.17.1-11.35
linux-image-2.6.17-11-generic - 2.6.17.1-11.35
linux-image-2.6.17-11-powerpc - 2.6.17.1-11.35
linux-image-2.6.17-11-powerpc-smp - 2.6.17.1-11.35
linux-image-2.6.17-11-powerpc64-smp - 2.6.17.1-11.35
linux-image-2.6.17-11-server - 2.6.17.1-11.35
linux-image-2.6.17-11-server-bigiron - 2.6.17.1-11.35
linux-image-2.6.17-11-sparc64 - 2.6.17.1-11.35
linux-image-2.6.17-11-sparc64-smp - 2.6.17.1-11.35
Ubuntu 6.06 LTS
linux-image-2.6.15-28-386 - 2.6.15-28.51
linux-image-2.6.15-28-686 - 2.6.15-28.51
linux-image-2.6.15-28-amd64-generic - 2.6.15-28.51
linux-image-2.6.15-28-amd64-k8 - 2.6.15-28.51
linux-image-2.6.15-28-amd64-server - 2.6.15-28.51
linux-image-2.6.15-28-amd64-xeon - 2.6.15-28.51
linux-image-2.6.15-28-k7 - 2.6.15-28.51
linux-image-2.6.15-28-powerpc - 2.6.15-28.51
linux-image-2.6.15-28-powerpc-smp - 2.6.15-28.51
linux-image-2.6.15-28-powerpc64-smp - 2.6.15-28.51
linux-image-2.6.15-28-server - 2.6.15-28.51
linux-image-2.6.15-28-server-bigiron - 2.6.15-28.51
linux-image-2.6.15-28-sparc64 - 2.6.15-28.51
linux-image-2.6.15-28-sparc64-smp - 2.6.15-28.51
Ubuntu 5.10
linux-image-2.6.12-10-386 - 2.6.12-10.45
linux-image-2.6.12-10-686 - 2.6.12-10.45
linux-image-2.6.12-10-686-smp - 2.6.12-10.45
linux-image-2.6.12-10-amd64-generic - 2.6.12-10.45
linux-image-2.6.12-10-amd64-k8 - 2.6.12-10.45
linux-image-2.6.12-10-amd64-k8-smp - 2.6.12-10.45
linux-image-2.6.12-10-amd64-xeon - 2.6.12-10.45
linux-image-2.6.12-10-k7 - 2.6.12-10.45
linux-image-2.6.12-10-k7-smp - 2.6.12-10.45
linux-image-2.6.12-10-powerpc - 2.6.12-10.45
linux-image-2.6.12-10-powerpc-smp - 2.6.12-10.45
linux-image-2.6.12-10-powerpc64-smp - 2.6.12-10.45
linux-patch-ubuntu-2.6.12 - 2.6.12-10.45

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

After a standard system upgrade you need to reboot your computer to effect the necessary changes.

ATTENTION: Due to an unavoidable ABI change the Ubuntu 6.06 and Ubuntu 6.10 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 (linux-386, linux-powerpc, linux-amd64-generic), a standard system upgrade will automatically perform this as well.

References