USN-486-1: Linux kernel vulnerabilities

18 July 2007

linux-source-2.6.17 vulnerabilities

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

  • Ubuntu 6.10

Software Description


The compat_sys_mount function allowed local users to cause a denial of service when mounting a smbfs filesystem in compatibility mode. (CVE-2006-7203)

The Omnikey CardMan 4040 driver (cm4040_cs) did not limit the size of buffers passed to read() and write(). A local attacker could exploit this to execute arbitrary code with kernel privileges. (CVE-2007-0005)

Due to a variable handling flaw in the ipv6_getsockopt_sticky() function a local attacker could exploit the getsockopt() calls to read arbitrary kernel memory. This could disclose sensitive data. (CVE-2007-1000)

Ilja van Sprundel discovered that Bluetooth setsockopt calls could leak kernel memory contents via an uninitialized stack buffer. A local attacker could exploit this flaw to view sensitive kernel information. (CVE-2007-1353)

A flaw was discovered in the handling of netlink messages. Local attackers could cause infinite recursion leading to a denial of service. (CVE-2007-1861)

A flaw was discovered in the IPv6 stack’s handling of type 0 route headers. By sending a specially crafted IPv6 packet, a remote attacker could cause a denial of service between two IPv6 hosts. (CVE-2007-2242)

The random number generator was hashing a subset of the available entropy, leading to slightly less random numbers. Additionally, systems without an entropy source would be seeded with the same inputs at boot time, leading to a repeatable series of random numbers. (CVE-2007-2453)

A flaw was discovered in the PPP over Ethernet implementation. Local attackers could manipulate ioctls and cause kernel memory consumption leading to a denial of service. (CVE-2007-2525)

An integer underflow was discovered in the cpuset filesystem. If mounted, local attackers could obtain kernel memory using large file offsets while reading the tasks file. This could disclose sensitive data. (CVE-2007-2875)

Vilmos Nebehaj discovered that the SCTP netfilter code did not correctly validate certain states. A remote attacker could send a specially crafted packet causing a denial of service. (CVE-2007-2876)

Luca Tettamanti discovered a flaw in the VFAT compat ioctls on 64-bit systems. A local attacker could corrupt a kernel_dirent struct and cause a denial of service. (CVE-2007-2878)

Update instructions

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

Ubuntu 6.10
linux-image-2.6.17-12-386 -
linux-image-2.6.17-12-generic -
linux-image-2.6.17-12-hppa32 -
linux-image-2.6.17-12-hppa64 -
linux-image-2.6.17-12-itanium -
linux-image-2.6.17-12-mckinley -
linux-image-2.6.17-12-powerpc -
linux-image-2.6.17-12-powerpc-smp -
linux-image-2.6.17-12-powerpc64-smp -
linux-image-2.6.17-12-server -
linux-image-2.6.17-12-server-bigiron -
linux-image-2.6.17-12-sparc64 -
linux-image-2.6.17-12-sparc64-smp -

To update your system, please follow these instructions:

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 6.10 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, etc), a standard system upgrade will automatically perform this as well.