USN-3823-1: Linux kernel vulnerabilities
linux vulnerabilities
A security issue affects these releases of Ubuntu and its derivatives:
- Ubuntu 12.04 ESM
Summary
Several security issues were mitigated in the Linux kernel.
Software Description
- linux – Linux kernel
Details
It was discovered that memory present in the L1 data cache of an Intel CPU
core may be exposed to a malicious process that is executing on the CPU
core. This vulnerability is also known as L1 Terminal Fault (L1TF). A local
attacker in a guest virtual machine could use this to expose sensitive
information (memory from other guests or the host OS). (CVE-2018-3646)
It was discovered that memory present in the L1 data cache of an Intel CPU
core may be exposed to a malicious process that is executing on the CPU
core. This vulnerability is also known as L1 Terminal Fault (L1TF). A local
attacker could use this to expose sensitive information (memory from the
kernel or other processes). (CVE-2018-3620)
Update instructions
The problem can be corrected by updating your system to the following package versions:
- Ubuntu 12.04 ESM
- linux-image-3.2.0-137-generic – 3.2.0-137.183
- linux-image-3.2.0-137-generic-pae – 3.2.0-137.183
- linux-image-3.2.0-137-highbank – 3.2.0-137.183
- linux-image-3.2.0-137-omap – 3.2.0-137.183
- linux-image-3.2.0-137-powerpc-smp – 3.2.0-137.183
- linux-image-3.2.0-137-powerpc64-smp – 3.2.0-137.183
- linux-image-3.2.0-137-virtual – 3.2.0-137.183
- linux-image-generic – 3.2.0.137.152
- linux-image-generic-pae – 3.2.0.137.152
- linux-image-highbank – 3.2.0.137.152
- linux-image-omap – 3.2.0.137.152
- linux-image-powerpc – 3.2.0.137.152
- linux-image-powerpc-smp – 3.2.0.137.152
- linux-image-powerpc64-smp – 3.2.0.137.152
- linux-image-virtual – 3.2.0.137.152
To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.
Please note that the recommended mitigation for CVE-2018-3646 involves
updating processor microcode in addition to updating the kernel;
however, the kernel includes a fallback for processors that have not
received microcode updates.
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.