USN-311-1: Linux kernel vulnerabilities

Ubuntu Security Notice USN-311-1

11th July, 2006

linux-source-2.6.10/-2.6.12/-2.6.15 vulnerabilities

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

  • Ubuntu 6.06 LTS
  • Ubuntu 5.10
  • Ubuntu 5.04


A race condition was discovered in the do_add_counters() functions.
Processes which do not run with full root privileges, but have the
CAP_NET_ADMIN capability can exploit this to crash the machine or read
a random piece of kernel memory. In Ubuntu there are no packages that
are affected by this, so this can only be an issue for you if you use
third-party software that uses Linux capabilities. (CVE-2006-0039)

John Stultz discovered a faulty BUG_ON trigger in the handling of
POSIX timers. A local attacker could exploit this to trigger a kernel
oops and crash the machine. (CVE-2006-2445)

Dave Jones discovered that the PowerPC kernel did not perform certain
required access_ok() checks. A local user could exploit this to read
arbitrary kernel memory and crash the kernel on 64-bit systems, and
possibly read arbitrary kernel memory on 32-bit systems.

A design flaw was discovered in the prctl(PR_SET_DUMPABLE, ...) system
call, which allowed a local user to have core dumps created in a
directory he could not normally write to. This could be exploited to
drain available disk space on system partitions, or, under some
circumstances, to execute arbitrary code with full root privileges.
This flaw only affects Ubuntu 6.06 LTS. (CVE-2006-2451)

In addition, the Ubuntu 6.06 LTS update fixes a range of bugs.

Update instructions

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

Ubuntu 6.06 LTS:
linux-image-2.6.15-26-hppa32-smp 2.6.15-26.44
linux-image-2.6.15-26-powerpc64-smp 2.6.15-26.44
linux-image-2.6.15-26-hppa64 2.6.15-26.44
linux-image-2.6.15-26-386 2.6.15-26.44
linux-image-2.6.15-26-amd64-xeon 2.6.15-26.44
linux-image-2.6.15-26-amd64-server 2.6.15-26.44
linux-image-2.6.15-26-amd64-k8 2.6.15-26.44
linux-image-2.6.15-26-hppa64-smp 2.6.15-26.44
linux-image-2.6.15-26-k7 2.6.15-26.44
linux-image-2.6.15-26-server-bigiron 2.6.15-26.44
linux-image-2.6.15-26-powerpc 2.6.15-26.44
linux-image-2.6.15-26-mckinley-smp 2.6.15-26.44
linux-image-2.6.15-26-amd64-generic 2.6.15-26.44
linux-image-2.6.15-26-server 2.6.15-26.44
linux-image-2.6.15-26-mckinley 2.6.15-26.44
linux-image-2.6.15-26-itanium-smp 2.6.15-26.44
linux-image-2.6.15-26-hppa32 2.6.15-26.44
linux-image-2.6.15-26-686 2.6.15-26.44
linux-image-2.6.15-26-itanium 2.6.15-26.44
linux-image-2.6.15-26-powerpc-smp 2.6.15-26.44
linux-image-2.6.15-26-sparc64 2.6.15-26.44
linux-image-2.6.15-26-sparc64-smp 2.6.15-26.44
Ubuntu 5.10:
linux-image-2.6.12-10-powerpc-smp 2.6.12-10.35
linux-patch-ubuntu-2.6.12 2.6.12-10.35
linux-image-2.6.12-10-hppa32 2.6.12-10.35
linux-image-2.6.12-10-itanium-smp 2.6.12-10.35
linux-image-2.6.12-10-sparc64 2.6.12-10.35
linux-image-2.6.12-10-powerpc64-smp 2.6.12-10.35
linux-image-2.6.12-10-hppa64-smp 2.6.12-10.35
linux-image-2.6.12-10-amd64-generic 2.6.12-10.35
linux-image-2.6.12-10-iseries-smp 2.6.12-10.35
linux-image-2.6.12-10-k7-smp 2.6.12-10.35
linux-image-2.6.12-10-amd64-xeon 2.6.12-10.35
linux-image-2.6.12-10-itanium 2.6.12-10.35
linux-image-2.6.12-10-hppa32-smp 2.6.12-10.35
linux-image-2.6.12-10-powerpc 2.6.12-10.35
linux-image-2.6.12-10-mckinley 2.6.12-10.35
linux-image-2.6.12-10-sparc64-smp 2.6.12-10.35
linux-image-2.6.12-10-hppa64 2.6.12-10.35
linux-image-2.6.12-10-amd64-k8-smp 2.6.12-10.35
linux-image-2.6.12-10-686 2.6.12-10.35
linux-image-2.6.12-10-686-smp 2.6.12-10.35
linux-image-2.6.12-10-k7 2.6.12-10.35
linux-image-2.6.12-10-mckinley-smp 2.6.12-10.35
linux-image-2.6.12-10-386 2.6.12-10.35
linux-image-2.6.12-10-amd64-k8 2.6.12-10.35
Ubuntu 5.04:
linux-patch-ubuntu-2.6.10 2.6.10-34.21
linux-image-2.6.10-6-686 2.6.10-34.21
linux-image-2.6.10-6-powerpc 2.6.10-34.21
linux-image-2.6.10-6-itanium 2.6.10-34.21
linux-image-2.6.10-6-power4-smp 2.6.10-34.21
linux-image-2.6.10-6-sparc64-smp 2.6.10-34.21
linux-image-2.6.10-6-hppa64-smp 2.6.10-34.21
linux-image-2.6.10-6-power3-smp 2.6.10-34.21
linux-image-2.6.10-6-hppa32-smp 2.6.10-34.21
linux-image-2.6.10-6-386 2.6.10-34.21
linux-image-2.6.10-6-hppa32 2.6.10-34.21
linux-image-2.6.10-6-sparc64 2.6.10-34.21
linux-image-2.6.10-6-hppa64 2.6.10-34.21
linux-image-2.6.10-6-amd64-xeon 2.6.10-34.21
linux-image-2.6.10-6-itanium-smp 2.6.10-34.21
linux-image-2.6.10-6-powerpc-smp 2.6.10-34.21
linux-image-2.6.10-6-k7-smp 2.6.10-34.21
linux-image-2.6.10-6-power3 2.6.10-34.21
linux-image-2.6.10-6-k7 2.6.10-34.21
linux-image-2.6.10-6-power4 2.6.10-34.21
linux-image-2.6.10-6-mckinley 2.6.10-34.21
linux-image-2.6.10-6-686-smp 2.6.10-34.21
linux-image-2.6.10-6-amd64-k8-smp 2.6.10-34.21
linux-image-2.6.10-6-amd64-generic 2.6.10-34.21
linux-image-2.6.10-6-amd64-k8 2.6.10-34.21
linux-image-2.6.10-6-mckinley-smp 2.6.10-34.21

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 6.06 kernel
update has 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.


CVE-2006-0039, CVE-2006-2445, CVE-2006-2448, CVE-2006-2451