USN-4096-1: Linux kernel (AWS) vulnerability

Releases

• Ubuntu 19.04
• Ubuntu 18.04 ESM
• Ubuntu 16.04 ESM

Packages

• linux-aws - Linux kernel for Amazon Web Services (AWS) systems
• linux-aws-hwe - Linux kernel for Amazon Web Services (AWS-HWE) systems

Details

Andrei Vlad Lutas and Dan Lutas discovered that some x86 processors
incorrectly handle SWAPGS instructions during speculative execution. A
local attacker could use this to expose sensitive information (kernel
memory).

Update instructions

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

Ubuntu 19.04

• linux-image-5.0.0-1012-aws - 5.0.0-1012.13
• linux-image-aws - 5.0.0.1012.12

Ubuntu 18.04

• linux-image-4.15.0-1045-aws - 4.15.0-1045.47
• linux-image-aws - 4.15.0.1045.44

Ubuntu 16.04

• linux-image-4.15.0-1045-aws - 4.15.0-1045.47~16.04.1
• linux-image-aws-hwe - 4.15.0.1045.45

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

• CVE-2019-1125

Related notices

• USN-4095-1
• USN-4094-1
• USN-4095-2
• USN-4093-1