CVE-2020-27777
Published: 15 December 2020
A flaw was found in the way RTAS handled memory accesses in userspace to kernel communication. On a locked down (usually due to Secure Boot) guest system running on top of PowerVM or KVM hypervisors (pseries platform) a root like local user could use this flaw to further increase their privileges to that of a running kernel.
From the Ubuntu Security Team
Daniel Axtens discovered that PowerPC RTAS implementation in the Linux kernel did not properly restrict memory accesses in some situations. A privileged local attacker could use this to arbitrarily modify kernel memory, potentially bypassing kernel lockdown restrictions.
Notes
Author | Note |
---|---|
sbeattie | fix needs typo correction from lkml link in refs |
Priority
Status
Package | Release | Status |
---|---|---|
linux-aws-5.0 Launchpad, Ubuntu, Debian |
focal |
Does not exist
|
bionic |
Not vulnerable
(powerpc only)
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.10~rc1)
|
|
xenial |
Does not exist
|
|
linux-azure-edge Launchpad, Ubuntu, Debian |
focal |
Does not exist
|
bionic |
Not vulnerable
(powerpc only)
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.10~rc1)
|
|
xenial |
Does not exist
|
|
linux-snapdragon Launchpad, Ubuntu, Debian |
focal |
Does not exist
|
bionic |
Not vulnerable
(powerpc only)
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.10~rc1)
|
|
xenial |
Not vulnerable
(powerpc only)
|
|
linux-gke-5.0 Launchpad, Ubuntu, Debian |
bionic |
Not vulnerable
(powerpc only)
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.10~rc1)
|
|
xenial |
Does not exist
|
|
linux-hwe Launchpad, Ubuntu, Debian |
xenial |
Released
(4.15.0-129.132~16.04.1)
|
bionic |
Ignored
(replaced by linux-hwe-5.4)
|
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.10~rc1)
|
|
linux-gke-5.4 Launchpad, Ubuntu, Debian |
focal |
Does not exist
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
xenial |
Does not exist
|
|
upstream |
Released
(5.10~rc1)
|
|
bionic |
Released
(5.4.0-1033.35~18.04.1)
|
|
linux-gkeop-5.4 Launchpad, Ubuntu, Debian |
focal |
Does not exist
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
xenial |
Does not exist
|
|
upstream |
Released
(5.10~rc1)
|
|
bionic |
Released
(5.4.0-1008.9~18.04.1)
|
|
linux-aws Launchpad, Ubuntu, Debian |
focal |
Not vulnerable
(powerpc only)
|
groovy |
Not vulnerable
(powerpc only)
|
|
bionic |
Not vulnerable
(powerpc only)
|
|
trusty |
Not vulnerable
(powerpc only)
|
|
upstream |
Released
(5.10~rc1)
|
|
xenial |
Not vulnerable
(powerpc only)
|
|
linux-hwe-5.8 Launchpad, Ubuntu, Debian |
upstream |
Released
(5.10~rc1)
|
bionic |
Does not exist
|
|
focal |
Released
(5.8.0-44.50~20.04.1)
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
xenial |
Does not exist
|
|
linux-dell300x Launchpad, Ubuntu, Debian |
focal |
Does not exist
|
trusty |
Does not exist
|
|
xenial |
Does not exist
|
|
upstream |
Released
(5.10~rc1)
|
|
bionic |
Released
(4.15.0-1010.14)
|
|
groovy |
Does not exist
|
|
linux-gkeop Launchpad, Ubuntu, Debian |
focal |
Not vulnerable
(5.4.0-1008.9)
|
upstream |
Released
(5.10~rc1)
|
|
bionic |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
xenial |
Does not exist
|
|
linux-oem-5.10 Launchpad, Ubuntu, Debian |
focal |
Not vulnerable
(5.10.0-1008.9)
|
upstream |
Released
(5.10~rc1)
|
|
bionic |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
xenial |
Does not exist
|
|
linux Launchpad, Ubuntu, Debian |
bionic |
Released
(4.15.0-129.132)
|
focal |
Released
(5.4.0-59.65)
|
|
groovy |
Released
(5.8.0-44.50)
|
|
trusty |
Ignored
(was needs-triage ESM criteria)
|
|
upstream |
Released
(5.10~rc1)
|
|
xenial |
Released
(4.4.0-201.233)
|
|
Patches: Introduced by 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 |
||
linux-aws-5.3 Launchpad, Ubuntu, Debian |
bionic |
Not vulnerable
(powerpc only)
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.10~rc1)
|
|
xenial |
Does not exist
|
|
linux-aws-5.4 Launchpad, Ubuntu, Debian |
bionic |
Not vulnerable
(powerpc only)
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.10~rc1)
|
|
xenial |
Does not exist
|
|
linux-aws-hwe Launchpad, Ubuntu, Debian |
bionic |
Does not exist
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.10~rc1)
|
|
xenial |
Not vulnerable
(powerpc only)
|
|
linux-azure Launchpad, Ubuntu, Debian |
bionic |
Not vulnerable
(powerpc only)
|
focal |
Not vulnerable
(powerpc only)
|
|
groovy |
Not vulnerable
(powerpc only)
|
|
trusty |
Not vulnerable
(powerpc only)
|
|
upstream |
Released
(5.10~rc1)
|
|
xenial |
Not vulnerable
(powerpc only)
|
|
linux-azure-4.15 Launchpad, Ubuntu, Debian |
bionic |
Not vulnerable
(powerpc only)
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.10~rc1)
|
|
xenial |
Does not exist
|
|
linux-azure-5.3 Launchpad, Ubuntu, Debian |
bionic |
Not vulnerable
(powerpc only)
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.10~rc1)
|
|
xenial |
Does not exist
|
|
linux-azure-5.4 Launchpad, Ubuntu, Debian |
bionic |
Not vulnerable
(powerpc only)
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.10~rc1)
|
|
xenial |
Does not exist
|
|
linux-gcp Launchpad, Ubuntu, Debian |
bionic |
Not vulnerable
(powerpc only)
|
focal |
Not vulnerable
(powerpc only)
|
|
groovy |
Not vulnerable
(powerpc only)
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.10~rc1)
|
|
xenial |
Not vulnerable
(powerpc only)
|
|
linux-gcp-4.15 Launchpad, Ubuntu, Debian |
bionic |
Not vulnerable
(powerpc only)
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.10~rc1)
|
|
xenial |
Does not exist
|
|
linux-gcp-5.3 Launchpad, Ubuntu, Debian |
bionic |
Not vulnerable
(powerpc only)
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.10~rc1)
|
|
xenial |
Does not exist
|
|
linux-gcp-5.4 Launchpad, Ubuntu, Debian |
bionic |
Not vulnerable
(powerpc only)
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.10~rc1)
|
|
xenial |
Does not exist
|
|
linux-gcp-edge Launchpad, Ubuntu, Debian |
bionic |
Not vulnerable
(powerpc only)
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.10~rc1)
|
|
xenial |
Does not exist
|
|
linux-gke-4.15 Launchpad, Ubuntu, Debian |
bionic |
Not vulnerable
(powerpc only)
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.10~rc1)
|
|
xenial |
Does not exist
|
|
linux-gke-5.3 Launchpad, Ubuntu, Debian |
bionic |
Not vulnerable
(powerpc only)
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.10~rc1)
|
|
xenial |
Does not exist
|
|
linux-hwe-5.4 Launchpad, Ubuntu, Debian |
bionic |
Released
(5.4.0-59.65~18.04.1)
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.10~rc1)
|
|
xenial |
Does not exist
|
|
linux-hwe-edge Launchpad, Ubuntu, Debian |
bionic |
Ignored
(superseded by linux-hwe-5.4)
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.10~rc1)
|
|
xenial |
Ignored
(superseded by linux-hwe)
|
|
linux-kvm Launchpad, Ubuntu, Debian |
bionic |
Not vulnerable
(powerpc only)
|
focal |
Not vulnerable
(powerpc only)
|
|
groovy |
Not vulnerable
(powerpc only)
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.10~rc1)
|
|
xenial |
Not vulnerable
(powerpc only)
|
|
linux-lts-trusty Launchpad, Ubuntu, Debian |
bionic |
Does not exist
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.10~rc1)
|
|
xenial |
Does not exist
|
|
linux-lts-xenial Launchpad, Ubuntu, Debian |
bionic |
Does not exist
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Released
(4.4.0-201.233~14.04.1)
Available with Ubuntu Pro or Ubuntu Pro (Infra-only) |
|
upstream |
Released
(5.10~rc1)
|
|
xenial |
Does not exist
|
|
linux-oem Launchpad, Ubuntu, Debian |
bionic |
Not vulnerable
(powerpc only)
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.10~rc1)
|
|
xenial |
Not vulnerable
(powerpc only)
|
|
linux-oem-5.6 Launchpad, Ubuntu, Debian |
bionic |
Does not exist
|
focal |
Not vulnerable
(powerpc only)
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.10~rc1)
|
|
xenial |
Does not exist
|
|
linux-oem-osp1 Launchpad, Ubuntu, Debian |
bionic |
Not vulnerable
(powerpc only)
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.10~rc1)
|
|
xenial |
Does not exist
|
|
linux-oracle Launchpad, Ubuntu, Debian |
bionic |
Not vulnerable
(powerpc only)
|
focal |
Not vulnerable
(powerpc only)
|
|
groovy |
Not vulnerable
(powerpc only)
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.10~rc1)
|
|
xenial |
Not vulnerable
(powerpc only)
|
|
linux-oracle-5.0 Launchpad, Ubuntu, Debian |
bionic |
Not vulnerable
(powerpc only)
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.10~rc1)
|
|
xenial |
Does not exist
|
|
linux-oracle-5.3 Launchpad, Ubuntu, Debian |
bionic |
Not vulnerable
(powerpc only)
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.10~rc1)
|
|
xenial |
Does not exist
|
|
linux-oracle-5.4 Launchpad, Ubuntu, Debian |
bionic |
Not vulnerable
(powerpc only)
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.10~rc1)
|
|
xenial |
Does not exist
|
|
linux-raspi Launchpad, Ubuntu, Debian |
bionic |
Does not exist
|
focal |
Not vulnerable
(powerpc only)
|
|
groovy |
Not vulnerable
(powerpc only)
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.10~rc1)
|
|
xenial |
Does not exist
|
|
linux-raspi-5.4 Launchpad, Ubuntu, Debian |
bionic |
Not vulnerable
(powerpc only)
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.10~rc1)
|
|
xenial |
Does not exist
|
|
linux-raspi2 Launchpad, Ubuntu, Debian |
bionic |
Not vulnerable
(powerpc only)
|
focal |
Not vulnerable
(powerpc only)
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.10~rc1)
|
|
xenial |
Not vulnerable
(powerpc only)
|
|
linux-raspi2-5.3 Launchpad, Ubuntu, Debian |
bionic |
Not vulnerable
(powerpc only)
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.10~rc1)
|
|
xenial |
Does not exist
|
|
linux-riscv Launchpad, Ubuntu, Debian |
bionic |
Does not exist
|
focal |
Not vulnerable
(powerpc only)
|
|
groovy |
Not vulnerable
(powerpc only)
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.10~rc1)
|
|
xenial |
Does not exist
|
Severity score breakdown
Parameter | Value |
---|---|
Base score | 6.7 |
Attack vector | Local |
Attack complexity | Low |
Privileges required | High |
User interaction | None |
Scope | Unchanged |
Confidentiality | High |
Integrity impact | High |
Availability impact | High |
Vector | CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H |
References
- https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-27777
- https://git.kernel.org/linus/bd59380c5ba4147dcbaad3e582b55ccfd120b764
- https://lkml.org/lkml/2020/12/8/950
- https://ubuntu.com/security/notices/USN-4679-1
- https://ubuntu.com/security/notices/USN-4680-1
- https://ubuntu.com/security/notices/USN-4708-1
- https://ubuntu.com/security/notices/USN-4751-1
- NVD
- Launchpad
- Debian