USN-2909-1: Linux kernel (Utopic HWE) vulnerabilities
22 February 2016
Several security issues were fixed in the kernel.
Releases
Packages
- linux-lts-utopic - Linux hardware enablement kernel from Utopic
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'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)
Update instructions
The problem can be corrected by updating your system to the following package versions:
Ubuntu 14.04
-
linux-image-3.16.0-62-generic
-
3.16.0-62.82~14.04.1
-
linux-image-3.16.0-62-generic-lpae
-
3.16.0-62.82~14.04.1
-
linux-image-3.16.0-62-lowlatency
-
3.16.0-62.82~14.04.1
-
linux-image-3.16.0-62-powerpc-e500mc
-
3.16.0-62.82~14.04.1
-
linux-image-3.16.0-62-powerpc-smp
-
3.16.0-62.82~14.04.1
-
linux-image-3.16.0-62-powerpc64-emb
-
3.16.0-62.82~14.04.1
-
linux-image-3.16.0-62-powerpc64-smp
-
3.16.0-62.82~14.04.1
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.