Ubuntu Security Notice 2444-1 - An information leak in the Linux kernel was discovered that could leak the high 16 bits of the kernel stack address on 32-bit Kernel Virtual Machine (KVM) paravirt guests. A user in the guest OS could exploit this leak to obtain information that could potentially be used to aid in attacking the kernel. Rabin Vincent, Robert Swiecki, Russell King discovered that the ftrace subsystem of the Linux kernel does not properly handle private syscall numbers. A local user could exploit this flaw to cause a denial of service (OOPS). Various other issues were also addressed.
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Ubuntu Security Notice USN-2444-1
December 12, 2014
linux-ti-omap4 vulnerabilities
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A security issue affects these releases of Ubuntu and its derivatives:
- Ubuntu 12.04 LTS
Summary:
Several security issues were fixed in the kernel.
Software Description:
- linux-ti-omap4: Linux kernel for OMAP4
Details:
An information leak in the Linux kernel was discovered that could leak the
high 16 bits of the kernel stack address on 32-bit Kernel Virtual Machine
(KVM) paravirt guests. A user in the guest OS could exploit this leak to
obtain information that could potentially be used to aid in attacking the
kernel. (CVE-2014-8134)
Rabin Vincent, Robert Swiecki, Russell King discovered that the ftrace
subsystem of the Linux kernel does not properly handle private syscall
numbers. A local user could exploit this flaw to cause a denial of service
(OOPS). (CVE-2014-7826)
Rabin Vincent, Robert Swiecki, Russell Kinglaw discovered a flaw in how the
perf subsystem of the Linux kernel handles private systecall numbers. A
local user could exploit this to cause a denial of service (OOPS) or bypass
ASLR protections via a crafted application. (CVE-2014-7825)
A null pointer dereference flaw was discovered in the the Linux kernel's
SCTP implementation when ASCONF is used. A remote attacker could exploit
this flaw to cause a denial of service (system crash) via a malformed INIT
chunk. (CVE-2014-7841)
A stack buffer overflow was discovered in the ioctl command handling for
the Technotrend/Hauppauge USB DEC devices driver. A local user could
exploit this flaw to cause a denial of service (system crash) or possibly
gain privileges. (CVE-2014-8884)
Andy Lutomirski discovered that the Linux kernel does not properly handle
faults associated with the Stack Segment (SS) register on the x86
architecture. A local attacker could exploit this flaw to cause a denial of
service (panic). (CVE-2014-9090)
Update instructions:
The problem can be corrected by updating your system to the following
package versions:
Ubuntu 12.04 LTS:
linux-image-3.2.0-1457-omap4 3.2.0-1457.77
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.
References:
http://www.ubuntu.com/usn/usn-2444-1
CVE-2014-7825, CVE-2014-7826, CVE-2014-7841, CVE-2014-8134,
CVE-2014-8884, CVE-2014-9090
Package Information:
https://launchpad.net/ubuntu/+source/linux-ti-omap4/3.2.0-1457.77