CVE-2018-20784

Published: 22 February 2019

In the Linux kernel before 4.20.2, kernel/sched/fair.c mishandles leaf cfs_rq's, which allows attackers to cause a denial of service (infinite loop in update_blocked_averages) or possibly have unspecified other impact by inducing a high load.

From the Ubuntu security team

Zhipeng Xie discovered that an infinite loop could be triggered in the CFS Linux kernel process scheduler. A local attacker could possibly use this to cause a denial of service.

Priority

Medium

CVSS 3 base score: 9.8

Status

Package Release Status
linux
Launchpad, Ubuntu, Debian
Upstream
Released (5.0~rc1)
Ubuntu 20.04 LTS (Focal Fossa) Not vulnerable
(5.4.0-9.12)
Ubuntu 18.04 LTS (Bionic Beaver)
Released (4.15.0-60.67)
Ubuntu 16.04 LTS (Xenial Xerus)
Released (4.4.0-170.199)
Ubuntu 14.04 ESM (Trusty Tahr) Not vulnerable
(3.11.0-12.19)
Ubuntu 12.04 ESM (Precise Pangolin) Ignored
(was needed ESM criteria)
Patches:
Introduced by a9e7f6544b9cebdae54d29f87a7ba2a83c0471b5
Fixed by c40f7d74c741a907cfaeb73a7697081881c497d0
linux-lts-trusty
Launchpad, Ubuntu, Debian
Upstream
Released (5.0~rc1)
Ubuntu 20.04 LTS (Focal Fossa) Does not exist

Ubuntu 18.04 LTS (Bionic Beaver) Does not exist

Ubuntu 16.04 LTS (Xenial Xerus) Does not exist

Ubuntu 14.04 ESM (Trusty Tahr) Does not exist

Ubuntu 12.04 ESM (Precise Pangolin) Ignored
(was needed ESM criteria)
linux-goldfish
Launchpad, Ubuntu, Debian
Upstream
Released (5.0~rc1)
Ubuntu 20.04 LTS (Focal Fossa) Does not exist

Ubuntu 18.04 LTS (Bionic Beaver) Does not exist

Ubuntu 16.04 LTS (Xenial Xerus) Ignored
(end-of-life)
Ubuntu 14.04 ESM (Trusty Tahr) Does not exist
(trusty was ignored [abandoned])
Ubuntu 12.04 ESM (Precise Pangolin) Does not exist

linux-grouper
Launchpad, Ubuntu, Debian
Upstream
Released (5.0~rc1)
Ubuntu 20.04 LTS (Focal Fossa) Does not exist

Ubuntu 18.04 LTS (Bionic Beaver) Does not exist

Ubuntu 16.04 LTS (Xenial Xerus) Does not exist

Ubuntu 14.04 ESM (Trusty Tahr) Does not exist
(trusty was ignored [abandoned])
Ubuntu 12.04 ESM (Precise Pangolin) Does not exist

linux-maguro
Launchpad, Ubuntu, Debian
Upstream
Released (5.0~rc1)
Ubuntu 20.04 LTS (Focal Fossa) Does not exist

Ubuntu 18.04 LTS (Bionic Beaver) Does not exist

Ubuntu 16.04 LTS (Xenial Xerus) Does not exist

Ubuntu 14.04 ESM (Trusty Tahr) Does not exist
(trusty was ignored [abandoned])
Ubuntu 12.04 ESM (Precise Pangolin) Does not exist

linux-mako
Launchpad, Ubuntu, Debian
Upstream
Released (5.0~rc1)
Ubuntu 20.04 LTS (Focal Fossa) Does not exist

Ubuntu 18.04 LTS (Bionic Beaver) Does not exist

Ubuntu 16.04 LTS (Xenial Xerus) Ignored
(abandoned)
Ubuntu 14.04 ESM (Trusty Tahr) Does not exist
(trusty was ignored [abandoned])
Ubuntu 12.04 ESM (Precise Pangolin) Does not exist

linux-manta
Launchpad, Ubuntu, Debian
Upstream
Released (5.0~rc1)
Ubuntu 20.04 LTS (Focal Fossa) Does not exist

Ubuntu 18.04 LTS (Bionic Beaver) Does not exist

Ubuntu 16.04 LTS (Xenial Xerus) Does not exist

Ubuntu 14.04 ESM (Trusty Tahr) Does not exist
(trusty was ignored [abandoned])
Ubuntu 12.04 ESM (Precise Pangolin) Does not exist

linux-flo
Launchpad, Ubuntu, Debian
Upstream
Released (5.0~rc1)
Ubuntu 20.04 LTS (Focal Fossa) Does not exist

Ubuntu 18.04 LTS (Bionic Beaver) Does not exist

Ubuntu 16.04 LTS (Xenial Xerus) Ignored
(abandoned)
Ubuntu 14.04 ESM (Trusty Tahr) Does not exist
(trusty was ignored [abandoned])
Ubuntu 12.04 ESM (Precise Pangolin) Does not exist

linux-raspi2
Launchpad, Ubuntu, Debian
Upstream
Released (5.0~rc1)
Ubuntu 20.04 LTS (Focal Fossa) Not vulnerable
(5.4.0-1004.4)
Ubuntu 18.04 LTS (Bionic Beaver)
Released (4.15.0-1044.47)
Ubuntu 16.04 LTS (Xenial Xerus)
Released (4.4.0-1126.135)
Ubuntu 14.04 ESM (Trusty Tahr) Does not exist

Ubuntu 12.04 ESM (Precise Pangolin) Does not exist

linux-lts-utopic
Launchpad, Ubuntu, Debian
Upstream
Released (5.0~rc1)
Ubuntu 20.04 LTS (Focal Fossa) Does not exist

Ubuntu 18.04 LTS (Bionic Beaver) Does not exist

Ubuntu 16.04 LTS (Xenial Xerus) Does not exist

Ubuntu 14.04 ESM (Trusty Tahr) Does not exist
(trusty was ignored [end-of-life])
Ubuntu 12.04 ESM (Precise Pangolin) Does not exist

linux-lts-vivid
Launchpad, Ubuntu, Debian
Upstream
Released (5.0~rc1)
Ubuntu 20.04 LTS (Focal Fossa) Does not exist

Ubuntu 18.04 LTS (Bionic Beaver) Does not exist

Ubuntu 16.04 LTS (Xenial Xerus) Does not exist

Ubuntu 14.04 ESM (Trusty Tahr) Does not exist
(trusty was ignored [end-of-life])
Ubuntu 12.04 ESM (Precise Pangolin) Does not exist

linux-lts-wily
Launchpad, Ubuntu, Debian
Upstream
Released (5.0~rc1)
Ubuntu 20.04 LTS (Focal Fossa) Does not exist

Ubuntu 18.04 LTS (Bionic Beaver) Does not exist

Ubuntu 16.04 LTS (Xenial Xerus) Does not exist

Ubuntu 14.04 ESM (Trusty Tahr) Does not exist
(trusty was ignored [end-of-life])
Ubuntu 12.04 ESM (Precise Pangolin) Does not exist

linux-lts-xenial
Launchpad, Ubuntu, Debian
Upstream
Released (5.0~rc1)
Ubuntu 20.04 LTS (Focal Fossa) Does not exist

Ubuntu 18.04 LTS (Bionic Beaver) Does not exist

Ubuntu 16.04 LTS (Xenial Xerus) Does not exist

Ubuntu 14.04 ESM (Trusty Tahr)
Released (4.4.0-170.199~14.04.1)
Ubuntu 12.04 ESM (Precise Pangolin) Does not exist

linux-snapdragon
Launchpad, Ubuntu, Debian
Upstream
Released (5.0~rc1)
Ubuntu 20.04 LTS (Focal Fossa) Does not exist

Ubuntu 18.04 LTS (Bionic Beaver)
Released (4.15.0-1062.69)
Ubuntu 16.04 LTS (Xenial Xerus)
Released (4.4.0-1130.138)
Ubuntu 14.04 ESM (Trusty Tahr) Does not exist

Ubuntu 12.04 ESM (Precise Pangolin) Does not exist

linux-aws
Launchpad, Ubuntu, Debian
Upstream
Released (5.0~rc1)
Ubuntu 20.04 LTS (Focal Fossa) Not vulnerable
(5.4.0-1004.4)
Ubuntu 18.04 LTS (Bionic Beaver)
Released (4.15.0-1047.49)
Ubuntu 16.04 LTS (Xenial Xerus)
Released (4.4.0-1099.110)
Ubuntu 14.04 ESM (Trusty Tahr)
Released (4.4.0-1059.63)
Ubuntu 12.04 ESM (Precise Pangolin) Does not exist

linux-hwe
Launchpad, Ubuntu, Debian
Upstream
Released (5.0~rc1)
Ubuntu 20.04 LTS (Focal Fossa) Does not exist

Ubuntu 18.04 LTS (Bionic Beaver)
Released (5.0.0-23.24~18.04.1)
Ubuntu 16.04 LTS (Xenial Xerus)
Released (4.15.0-60.67~16.04.1)
Ubuntu 14.04 ESM (Trusty Tahr) Does not exist

Ubuntu 12.04 ESM (Precise Pangolin) Does not exist

linux-hwe-edge
Launchpad, Ubuntu, Debian
Upstream
Released (5.0~rc1)
Ubuntu 20.04 LTS (Focal Fossa) Does not exist

Ubuntu 18.04 LTS (Bionic Beaver) Not vulnerable
(5.0.0-15.16~18.04.1)
Ubuntu 16.04 LTS (Xenial Xerus)
Released (4.15.0-60.67~16.04.1)
Ubuntu 14.04 ESM (Trusty Tahr) Does not exist

Ubuntu 12.04 ESM (Precise Pangolin) Does not exist

linux-gke
Launchpad, Ubuntu, Debian
Upstream
Released (5.0~rc1)
Ubuntu 20.04 LTS (Focal Fossa) Does not exist

Ubuntu 18.04 LTS (Bionic Beaver) Does not exist

Ubuntu 16.04 LTS (Xenial Xerus) Ignored
(end-of-life)
Ubuntu 14.04 ESM (Trusty Tahr) Does not exist

Ubuntu 12.04 ESM (Precise Pangolin) Does not exist

linux-gke-4.15
Launchpad, Ubuntu, Debian
Upstream
Released (5.0~rc1)
Ubuntu 20.04 LTS (Focal Fossa) Does not exist

Ubuntu 18.04 LTS (Bionic Beaver)
Released (4.15.0-1041.43)
Ubuntu 16.04 LTS (Xenial Xerus) Does not exist

Ubuntu 14.04 ESM (Trusty Tahr) Does not exist

Ubuntu 12.04 ESM (Precise Pangolin) Does not exist

linux-gke-5.0
Launchpad, Ubuntu, Debian
Upstream
Released (5.0~rc1)
Ubuntu 20.04 LTS (Focal Fossa) Does not exist

Ubuntu 18.04 LTS (Bionic Beaver) Not vulnerable
(5.0.0-1011.11~18.04.1)
Ubuntu 16.04 LTS (Xenial Xerus) Does not exist

Ubuntu 14.04 ESM (Trusty Tahr) Does not exist

Ubuntu 12.04 ESM (Precise Pangolin) Does not exist

linux-azure
Launchpad, Ubuntu, Debian
Upstream
Released (5.0~rc1)
Ubuntu 20.04 LTS (Focal Fossa) Not vulnerable
(5.4.0-1005.5)
Ubuntu 18.04 LTS (Bionic Beaver)
Released (5.0.0-1014.14~18.04.1)
Ubuntu 16.04 LTS (Xenial Xerus)
Released (4.15.0-1056.61)
Ubuntu 14.04 ESM (Trusty Tahr) Ignored
(was needed ESM criteria)
Ubuntu 12.04 ESM (Precise Pangolin) Does not exist

linux-azure-edge
Launchpad, Ubuntu, Debian
Upstream
Released (5.0~rc1)
Ubuntu 20.04 LTS (Focal Fossa) Does not exist

Ubuntu 18.04 LTS (Bionic Beaver)
Released (5.0.0-1014.14~18.04.1)
Ubuntu 16.04 LTS (Xenial Xerus)
Released (4.15.0-1056.61)
Ubuntu 14.04 ESM (Trusty Tahr) Does not exist

Ubuntu 12.04 ESM (Precise Pangolin) Does not exist

linux-gcp
Launchpad, Ubuntu, Debian
Upstream
Released (5.0~rc1)
Ubuntu 20.04 LTS (Focal Fossa) Not vulnerable
(5.4.0-1002.2)
Ubuntu 18.04 LTS (Bionic Beaver)
Released (4.15.0-1042.45)
Ubuntu 16.04 LTS (Xenial Xerus)
Released (4.15.0-1041.43)
Ubuntu 14.04 ESM (Trusty Tahr) Does not exist

Ubuntu 12.04 ESM (Precise Pangolin) Does not exist

linux-kvm
Launchpad, Ubuntu, Debian
Upstream
Released (5.0~rc1)
Ubuntu 20.04 LTS (Focal Fossa) Not vulnerable
(5.4.0-1003.3)
Ubuntu 18.04 LTS (Bionic Beaver)
Released (4.15.0-1043.43)
Ubuntu 16.04 LTS (Xenial Xerus)
Released (4.4.0-1063.70)
Ubuntu 14.04 ESM (Trusty Tahr) Does not exist

Ubuntu 12.04 ESM (Precise Pangolin) Does not exist

linux-euclid
Launchpad, Ubuntu, Debian
Upstream
Released (5.0~rc1)
Ubuntu 20.04 LTS (Focal Fossa) Does not exist

Ubuntu 18.04 LTS (Bionic Beaver) Does not exist

Ubuntu 16.04 LTS (Xenial Xerus) Ignored
(was needed ESM criteria)
Ubuntu 14.04 ESM (Trusty Tahr) Does not exist

Ubuntu 12.04 ESM (Precise Pangolin) Does not exist

linux-oem
Launchpad, Ubuntu, Debian
Upstream
Released (5.0~rc1)
Ubuntu 20.04 LTS (Focal Fossa) Does not exist

Ubuntu 18.04 LTS (Bionic Beaver)
Released (4.15.0-1056.65)
Ubuntu 16.04 LTS (Xenial Xerus) Ignored
(was needs-triage now end-of-life)
Ubuntu 14.04 ESM (Trusty Tahr) Does not exist

Ubuntu 12.04 ESM (Precise Pangolin) Does not exist

linux-gcp-edge
Launchpad, Ubuntu, Debian
Upstream
Released (5.0~rc1)
Ubuntu 20.04 LTS (Focal Fossa) Does not exist

Ubuntu 18.04 LTS (Bionic Beaver)
Released (4.15.0-1042.45)
Ubuntu 16.04 LTS (Xenial Xerus) Does not exist

Ubuntu 14.04 ESM (Trusty Tahr) Does not exist

Ubuntu 12.04 ESM (Precise Pangolin) Does not exist

linux-aws-hwe
Launchpad, Ubuntu, Debian
Upstream
Released (5.0~rc1)
Ubuntu 20.04 LTS (Focal Fossa) Does not exist

Ubuntu 18.04 LTS (Bionic Beaver) Does not exist

Ubuntu 16.04 LTS (Xenial Xerus)
Released (4.15.0-1047.49~16.04.1)
Ubuntu 14.04 ESM (Trusty Tahr) Does not exist

Ubuntu 12.04 ESM (Precise Pangolin) Does not exist

linux-oracle
Launchpad, Ubuntu, Debian
Upstream
Released (5.0~rc1)
Ubuntu 20.04 LTS (Focal Fossa) Not vulnerable
(5.4.0-1003.3)
Ubuntu 18.04 LTS (Bionic Beaver)
Released (4.15.0-1022.25)
Ubuntu 16.04 LTS (Xenial Xerus)
Released (4.15.0-1022.25~16.04.1)
Ubuntu 14.04 ESM (Trusty Tahr) Does not exist

Ubuntu 12.04 ESM (Precise Pangolin) Does not exist

linux-oem-osp1
Launchpad, Ubuntu, Debian
Upstream
Released (5.0~rc1)
Ubuntu 20.04 LTS (Focal Fossa) Does not exist

Ubuntu 18.04 LTS (Bionic Beaver) Not vulnerable
(5.0.0-1010.11)
Ubuntu 16.04 LTS (Xenial Xerus) Does not exist

Ubuntu 14.04 ESM (Trusty Tahr) Does not exist

Ubuntu 12.04 ESM (Precise Pangolin) Does not exist

linux-aws-5.0
Launchpad, Ubuntu, Debian
Upstream
Released (5.0~rc1)
Ubuntu 20.04 LTS (Focal Fossa) Does not exist

Ubuntu 18.04 LTS (Bionic Beaver) Not vulnerable
(5.0.0-1021.24~18.04.1)
Ubuntu 16.04 LTS (Xenial Xerus) Does not exist

Ubuntu 14.04 ESM (Trusty Tahr) Does not exist

Ubuntu 12.04 ESM (Precise Pangolin) Does not exist

linux-azure-5.3
Launchpad, Ubuntu, Debian
Upstream
Released (5.0~rc1)
Ubuntu 20.04 LTS (Focal Fossa) Does not exist

Ubuntu 18.04 LTS (Bionic Beaver) Not vulnerable
(5.3.0-1007.8~18.04.1)
Ubuntu 16.04 LTS (Xenial Xerus) Does not exist

Ubuntu 14.04 ESM (Trusty Tahr) Does not exist

Ubuntu 12.04 ESM (Precise Pangolin) Does not exist

linux-gcp-5.3
Launchpad, Ubuntu, Debian
Upstream
Released (5.0~rc1)
Ubuntu 20.04 LTS (Focal Fossa) Does not exist

Ubuntu 18.04 LTS (Bionic Beaver) Not vulnerable
(5.3.0-1008.9~18.04.1)
Ubuntu 16.04 LTS (Xenial Xerus) Does not exist

Ubuntu 14.04 ESM (Trusty Tahr) Does not exist

Ubuntu 12.04 ESM (Precise Pangolin) Does not exist

linux-oracle-5.0
Launchpad, Ubuntu, Debian
Upstream
Released (5.0~rc1)
Ubuntu 20.04 LTS (Focal Fossa) Does not exist

Ubuntu 18.04 LTS (Bionic Beaver) Not vulnerable
(5.0.0-1007.12~18.04.1)
Ubuntu 16.04 LTS (Xenial Xerus) Does not exist

Ubuntu 14.04 ESM (Trusty Tahr) Does not exist

Ubuntu 12.04 ESM (Precise Pangolin) Does not exist

linux-raspi2-5.3
Launchpad, Ubuntu, Debian
Upstream
Released (5.0~rc1)
Ubuntu 20.04 LTS (Focal Fossa) Does not exist

Ubuntu 18.04 LTS (Bionic Beaver) Not vulnerable
(5.3.0-1017.19~18.04.1)
Ubuntu 16.04 LTS (Xenial Xerus) Does not exist

Ubuntu 14.04 ESM (Trusty Tahr) Does not exist

Ubuntu 12.04 ESM (Precise Pangolin) Does not exist

linux-oem-5.4
Launchpad, Ubuntu, Debian
Upstream
Released (5.0~rc1)
Ubuntu 20.04 LTS (Focal Fossa) Not vulnerable
(5.4.0-1002.4)
Ubuntu 18.04 LTS (Bionic Beaver) Does not exist

Ubuntu 16.04 LTS (Xenial Xerus) Does not exist

Ubuntu 14.04 ESM (Trusty Tahr) Does not exist

Ubuntu 12.04 ESM (Precise Pangolin) Does not exist