CVE-2018-3646

Published: 14 August 2018

Systems with microprocessors utilizing speculative execution and address translations may allow unauthorized disclosure of information residing in the L1 data cache to an attacker with local user access with guest OS privilege via a terminal page fault and a side-channel analysis.

From the Ubuntu security team

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).

Priority

High

CVSS 3 base score: 5.6

Status

Package Release Status
intel-microcode
Launchpad, Ubuntu, Debian
Upstream Needed

Ubuntu 18.04 LTS (Bionic Beaver)
Released (3.20180807a.0ubuntu0.18.04.1)
linux
Launchpad, Ubuntu, Debian
Upstream
Released (4.19~rc1)
Ubuntu 18.04 LTS (Bionic Beaver)
Released (4.15.0-32.35)
Patches:
Introduced by 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2
Fixed by c595ceee45707f00f64f61c54fb64ef0cc0b4e85|local-2018-3646-fix
linux-aws
Launchpad, Ubuntu, Debian
Upstream
Released (4.19~rc1)
Ubuntu 18.04 LTS (Bionic Beaver)
Released (4.15.0-1019.19)
linux-aws-hwe
Launchpad, Ubuntu, Debian
Upstream
Released (4.19~rc1)
Ubuntu 18.04 LTS (Bionic Beaver) Does not exist

linux-azure
Launchpad, Ubuntu, Debian
Upstream
Released (4.19~rc1)
Ubuntu 18.04 LTS (Bionic Beaver)
Released (4.15.0-1021.21)
linux-azure-edge
Launchpad, Ubuntu, Debian
Upstream
Released (4.19~rc1)
Ubuntu 18.04 LTS (Bionic Beaver)
Released (4.15.0-1021.21)
linux-euclid
Launchpad, Ubuntu, Debian
Upstream
Released (4.19~rc1)
Ubuntu 18.04 LTS (Bionic Beaver) Does not exist

linux-flo
Launchpad, Ubuntu, Debian
Upstream Not vulnerable
(ARM is not affected)
Ubuntu 18.04 LTS (Bionic Beaver) Does not exist

linux-gcp
Launchpad, Ubuntu, Debian
Upstream
Released (4.19~rc1)
Ubuntu 18.04 LTS (Bionic Beaver)
Released (4.15.0-1017.18)
linux-gcp-edge
Launchpad, Ubuntu, Debian
Upstream
Released (4.19~rc1)
Ubuntu 18.04 LTS (Bionic Beaver) Not vulnerable
(4.18.0-1004.5~18.04.1)
linux-gke
Launchpad, Ubuntu, Debian
Upstream
Released (4.19~rc1)
Ubuntu 18.04 LTS (Bionic Beaver) Does not exist

linux-goldfish
Launchpad, Ubuntu, Debian
Upstream
Released (4.19~rc1)
Ubuntu 18.04 LTS (Bionic Beaver) Does not exist

linux-grouper
Launchpad, Ubuntu, Debian
Upstream Not vulnerable
(ARM is not affected)
Ubuntu 18.04 LTS (Bionic Beaver) Does not exist

linux-hwe
Launchpad, Ubuntu, Debian
Upstream
Released (4.19~rc1)
Ubuntu 18.04 LTS (Bionic Beaver) Not vulnerable
(4.18.0-13.14~18.04.1)
linux-hwe-edge
Launchpad, Ubuntu, Debian
Upstream
Released (4.19~rc1)
Ubuntu 18.04 LTS (Bionic Beaver) Not vulnerable
(4.18.0-12.13~18.04.1)
linux-kvm
Launchpad, Ubuntu, Debian
Upstream
Released (4.19~rc1)
Ubuntu 18.04 LTS (Bionic Beaver)
Released (4.15.0-1019.19)
linux-lts-trusty
Launchpad, Ubuntu, Debian
Upstream
Released (4.19~rc1)
Ubuntu 18.04 LTS (Bionic Beaver) Does not exist

linux-lts-utopic
Launchpad, Ubuntu, Debian
Upstream
Released (4.19~rc1)
Ubuntu 18.04 LTS (Bionic Beaver) Does not exist

linux-lts-vivid
Launchpad, Ubuntu, Debian
Upstream
Released (4.19~rc1)
Ubuntu 18.04 LTS (Bionic Beaver) Does not exist

linux-lts-wily
Launchpad, Ubuntu, Debian
Upstream
Released (4.19~rc1)
Ubuntu 18.04 LTS (Bionic Beaver) Does not exist

linux-lts-xenial
Launchpad, Ubuntu, Debian
Upstream
Released (4.19~rc1)
Ubuntu 18.04 LTS (Bionic Beaver) Does not exist

linux-maguro
Launchpad, Ubuntu, Debian
Upstream Not vulnerable
(ARM is not affected)
Ubuntu 18.04 LTS (Bionic Beaver) Does not exist

linux-mako
Launchpad, Ubuntu, Debian
Upstream Not vulnerable
(ARM is not affected)
Ubuntu 18.04 LTS (Bionic Beaver) Does not exist

linux-manta
Launchpad, Ubuntu, Debian
Upstream Not vulnerable
(ARM is not affected)
Ubuntu 18.04 LTS (Bionic Beaver) Does not exist

linux-oem
Launchpad, Ubuntu, Debian
Upstream
Released (4.19~rc1)
Ubuntu 18.04 LTS (Bionic Beaver)
Released (4.15.0-1015.18)
linux-oracle
Launchpad, Ubuntu, Debian
Upstream
Released (4.19~rc1)
Ubuntu 18.04 LTS (Bionic Beaver) Not vulnerable
(4.15.0-1007.9)
linux-raspi2
Launchpad, Ubuntu, Debian
Upstream Not vulnerable
(ARM is not affected)
Ubuntu 18.04 LTS (Bionic Beaver) Not vulnerable
(ARM is not affected)
linux-snapdragon
Launchpad, Ubuntu, Debian
Upstream Not vulnerable
(ARM is not affected)
Ubuntu 18.04 LTS (Bionic Beaver) Not vulnerable

Notes

AuthorNote
tyhicks
A microcode update will be provided to allow the kernel to flush the
L1D cache on VM entry. However, the kernel has a software fallback mechanism
in place when microcode updates are not available/installed.
The break-fix lines for this CVE are not complete since a large
number of patches are required to mitigate this issue. The commit(s) listed
are chosen as placeholders for automated CVE triage purposes.

References