USN-2908-2: Linux kernel (Wily HWE) vulnerabilities

22 February 2016

Several security issues were fixed in the kernel.

Reduce your security exposure

Ubuntu Pro provides ten-year security coverage to 25,000+ packages in Main and Universe repositories, and it is free for up to five machines.

Learn more about Ubuntu Pro

Releases

Packages

Details

halfdog discovered that OverlayFS, when mounting on top of a FUSE mount,
incorrectly propagated file attributes, including setuid. A local
unprivileged attacker could use this to gain privileges. (CVE-2016-1576)

halfdog discovered that OverlayFS in the Linux kernel incorrectly
propagated security sensitive extended attributes, such as POSIX ACLs. A
local unprivileged attacker could use this to gain privileges.
(CVE-2016-1575)

It was discovered that the Linux kernel did not properly enforce rlimits
for file descriptors sent over UNIX domain sockets. A local attacker could
use this to cause a denial of service. (CVE-2013-4312)

It was discovered that the Linux kernel's Filesystem in Userspace (FUSE)
implementation did not handle initial zero length segments properly. A
local attacker could use this to cause a denial of service (unkillable
task). (CVE-2015-8785)

Andy Lutomirski discovered a race condition in the Linux kernel's
translation lookaside buffer (TLB) handling of flush events. A local
attacker could use this to cause a denial of service or possibly leak
sensitive information. (CVE-2016-2069)

Reduce your security exposure

Ubuntu Pro provides ten-year security coverage to 25,000+ packages in Main and Universe repositories, and it is free for up to five machines.

Learn more about Ubuntu Pro

Update instructions

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

Ubuntu 14.04

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.
Unless you manually uninstalled the standard kernel metapackages
(e.g. linux-generic, linux-generic-lts-RELEASE, linux-virtual,
linux-powerpc), a standard system upgrade will automatically perform
this as well.

References

Related notices

Join the discussion

Need help with your security needs?

Ubuntu Pro provides up to ten-year security coverage for over 23,000 open-source packages within the Ubuntu Main and Universe repositories.

Talk to an expert to find out what would work best for you

Further reading