USN-3582-1: Linux kernel vulnerabilities
Ubuntu Security Notice USN-3582-1
22nd February, 2018
linux, linux-aws, linux-kvm, linux-raspi2, linux-snapdragon vulnerabilities
A security issue affects these releases of Ubuntu and its
derivatives:
- Ubuntu 16.04 LTS
Summary
Several security issues were fixed in the Linux kernel.
Software description
- linux
– Linux kernel - linux-aws
– Linux kernel for Amazon Web Services (AWS) systems - linux-kvm
– Linux kernel for cloud environments - linux-raspi2
– Linux kernel for Raspberry Pi 2 - linux-snapdragon
– Linux kernel for Snapdragon processors
Details
Mohamed Ghannam discovered that the IPv4 raw socket implementation in the
Linux kernel contained a race condition leading to uninitialized pointer
usage. A local attacker could use this to cause a denial of service or
possibly execute arbitrary code. (CVE-2017-17712)
Laurent Guerby discovered that the mbcache feature in the ext2 and ext4
filesystems in the Linux kernel improperly handled xattr block caching. A
local attacker could use this to cause a denial of service. (CVE-2015-8952)
Vitaly Mayatskikh discovered that the SCSI subsystem in the Linux kernel
did not properly track reference counts when merging buffers. A local
attacker could use this to cause a denial of service (memory exhaustion).
(CVE-2017-12190)
ChunYu Wang discovered that a use-after-free vulnerability existed in the
SCTP protocol implementation in the Linux kernel. A local attacker could
use this to cause a denial of service (system crash) or possibly execute
arbitrary code, (CVE-2017-15115)
Mohamed Ghannam discovered a use-after-free vulnerability in the DCCP
protocol implementation in the Linux kernel. A local attacker could use
this to cause a denial of service (system crash) or possibly execute
arbitrary code. (CVE-2017-8824)
USN-3540-1 mitigated CVE-2017-5715 (Spectre Variant 2) for the
amd64 architecture in Ubuntu 16.04 LTS. This update provides the
compiler-based retpoline kernel mitigation for the amd64 and i386
architectures. Original advisory details:
Jann Horn discovered that microprocessors utilizing speculative execution
and branch prediction may allow unauthorized memory reads via sidechannel
attacks. This flaw is known as Spectre. A local attacker could use this to
expose sensitive information, including kernel memory. (CVE-2017-5715)
Update instructions
The problem can be corrected by updating your system to the following
package version:
- Ubuntu 16.04 LTS:
- linux-image-powerpc-e500mc 4.4.0.116.122
-
linux-image-4.4.0-116-powerpc64-smp
4.4.0-116.140
-
linux-image-4.4.0-1052-aws
4.4.0-1052.61
-
linux-image-4.4.0-116-lowlatency
4.4.0-116.140
-
linux-image-4.4.0-1019-kvm
4.4.0-1019.24
- linux-image-snapdragon 4.4.0.1087.79
- linux-image-powerpc64-emb 4.4.0.116.122
- linux-image-generic 4.4.0.116.122
-
linux-image-4.4.0-116-generic
4.4.0-116.140
-
linux-image-4.4.0-116-generic-lpae
4.4.0-116.140
-
linux-image-4.4.0-116-powerpc-e500mc
4.4.0-116.140
-
linux-image-4.4.0-1085-raspi2
4.4.0-1085.93
- linux-image-aws 4.4.0.1052.54
- linux-image-kvm 4.4.0.1019.18
-
linux-image-4.4.0-116-powerpc-smp
4.4.0-116.140
- linux-image-raspi2 4.4.0.1085.85
- linux-image-powerpc-smp 4.4.0.116.122
-
linux-image-4.4.0-116-powerpc64-emb
4.4.0-116.140
- linux-image-generic-lpae 4.4.0.116.122
- linux-image-powerpc64-smp 4.4.0.116.122
-
linux-image-4.4.0-1087-snapdragon
4.4.0-1087.92
- linux-image-lowlatency 4.4.0.116.122
To update your system, please follow these instructions:
https://wiki.ubuntu.com/Security/Upgrades.
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.