CVE-2020-12656
Published: 5 May 2020
** DISPUTED ** gss_mech_free in net/sunrpc/auth_gss/gss_mech_switch.c in the rpcsec_gss_krb5 implementation in the Linux kernel through 5.6.10 lacks certain domain_release calls, leading to a memory leak. Note: This was disputed with the assertion that the issue does not grant any access not already available. It is a problem that on unloading a specific kernel module some memory is leaked, but loading kernel modules is a privileged operation. A user could also write a kernel module to consume any amount of memory they like and load that replicating the effect of this bug.
From the Ubuntu Security Team
It was discovered that the Kerberos SUNRPC GSS implementation in the Linux kernel did not properly deallocate memory on module unload. A local privileged attacker could possibly use this to cause a denial of service (memory exhaustion).
Notes
Author | Note |
---|---|
sbeattie | upstream generally treats module unload as an unsafe operation, which may explain a lack of progress in addressing the issue. |
Priority
Status
Package | Release | Status |
---|---|---|
linux-oem-5.6 Launchpad, Ubuntu, Debian |
focal |
Released
(5.6.0-1031.32)
|
groovy |
Does not exist
|
|
bionic |
Does not exist
|
|
eoan |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.8~rc1)
|
|
xenial |
Does not exist
|
|
linux-hwe Launchpad, Ubuntu, Debian |
focal |
Does not exist
|
groovy |
Does not exist
|
|
bionic |
Released
(5.3.0-64.58~18.04.1)
|
|
eoan |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.8~rc1)
|
|
xenial |
Released
(4.15.0-115.116~16.04.1)
|
|
linux Launchpad, Ubuntu, Debian |
bionic |
Released
(4.15.0-115.116)
|
eoan |
Ignored
(end of life)
|
|
focal |
Released
(5.4.0-45.49)
|
|
groovy |
Not vulnerable
(5.8.0-16.17)
|
|
trusty |
Ignored
(was needs-triage ESM criteria)
|
|
upstream |
Released
(5.8~rc1)
|
|
xenial |
Released
(4.4.0-186.216)
|
|
Patches: Introduced by 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 Introduced by 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 |
||
linux-aws Launchpad, Ubuntu, Debian |
bionic |
Released
(4.15.0-1080.84)
|
eoan |
Ignored
(end of life)
|
|
focal |
Released
(5.4.0-1022.22)
|
|
groovy |
Not vulnerable
(5.8.0-1004.4)
|
|
trusty |
Ignored
(was needs-triage ESM criteria)
|
|
upstream |
Released
(5.8~rc1)
|
|
xenial |
Released
(4.4.0-1111.123)
|
|
linux-aws-5.0 Launchpad, Ubuntu, Debian |
bionic |
Ignored
(end of life, was needs-triage)
|
eoan |
Does not exist
|
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.8~rc1)
|
|
xenial |
Does not exist
|
|
linux-aws-5.3 Launchpad, Ubuntu, Debian |
bionic |
Ignored
(end of life, was pending)
|
eoan |
Does not exist
|
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.8~rc1)
|
|
xenial |
Does not exist
|
|
linux-aws-5.4 Launchpad, Ubuntu, Debian |
bionic |
Released
(5.4.0-1022.22~18.04.1)
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.8~rc1)
|
|
xenial |
Does not exist
|
|
linux-aws-hwe Launchpad, Ubuntu, Debian |
bionic |
Does not exist
|
eoan |
Does not exist
|
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.8~rc1)
|
|
xenial |
Released
(4.15.0-1080.84~16.04.1)
|
|
linux-azure Launchpad, Ubuntu, Debian |
bionic |
Ignored
(end of life, was needs-triage)
|
eoan |
Ignored
(end of life)
|
|
focal |
Released
(5.4.0-1023.23)
|
|
groovy |
Not vulnerable
(5.8.0-1004.4)
|
|
trusty |
Released
(4.15.0-1093.103~14.04.1)
Available with Ubuntu Pro or Ubuntu Pro (Infra-only) |
|
upstream |
Released
(5.8~rc1)
|
|
xenial |
Released
(4.15.0-1093.103~16.04.1)
|
|
linux-azure-4.15 Launchpad, Ubuntu, Debian |
bionic |
Released
(4.15.0-1093.103)
|
eoan |
Does not exist
|
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.8~rc1)
|
|
xenial |
Does not exist
|
|
linux-azure-5.3 Launchpad, Ubuntu, Debian |
bionic |
Ignored
(end of life, was needs-triage)
|
eoan |
Does not exist
|
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.8~rc1)
|
|
xenial |
Does not exist
|
|
linux-azure-5.4 Launchpad, Ubuntu, Debian |
bionic |
Released
(5.4.0-1023.23~18.04.1)
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.8~rc1)
|
|
xenial |
Does not exist
|
|
linux-azure-edge Launchpad, Ubuntu, Debian |
bionic |
Ignored
(end of life, was needs-triage)
|
eoan |
Does not exist
|
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.8~rc1)
|
|
xenial |
Does not exist
|
|
linux-gcp Launchpad, Ubuntu, Debian |
bionic |
Ignored
(end of life, was needs-triage)
|
eoan |
Ignored
(end of life)
|
|
focal |
Released
(5.4.0-1022.22)
|
|
groovy |
Not vulnerable
(5.8.0-1002.2)
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.8~rc1)
|
|
xenial |
Released
(4.15.0-1081.92~16.04.1)
|
|
linux-gcp-4.15 Launchpad, Ubuntu, Debian |
bionic |
Released
(4.15.0-1081.92)
|
eoan |
Does not exist
|
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.8~rc1)
|
|
xenial |
Does not exist
|
|
linux-gcp-5.3 Launchpad, Ubuntu, Debian |
bionic |
Ignored
(end of life, was needs-triage)
|
eoan |
Does not exist
|
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.8~rc1)
|
|
xenial |
Does not exist
|
|
linux-gcp-5.4 Launchpad, Ubuntu, Debian |
bionic |
Released
(5.4.0-1022.22~18.04.1)
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.8~rc1)
|
|
xenial |
Does not exist
|
|
linux-gcp-edge Launchpad, Ubuntu, Debian |
bionic |
Ignored
(end of life, was needs-triage)
|
eoan |
Does not exist
|
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.8~rc1)
|
|
xenial |
Does not exist
|
|
linux-gke-4.15 Launchpad, Ubuntu, Debian |
bionic |
Released
(4.15.0-1067.70)
|
eoan |
Does not exist
|
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.8~rc1)
|
|
xenial |
Does not exist
|
|
linux-gke-5.0 Launchpad, Ubuntu, Debian |
bionic |
Released
(5.0.0-1045.46)
|
eoan |
Does not exist
|
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.8~rc1)
|
|
xenial |
Does not exist
|
|
linux-gke-5.3 Launchpad, Ubuntu, Debian |
bionic |
Released
(5.3.0-1032.34~18.04.1)
|
eoan |
Does not exist
|
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.8~rc1)
|
|
xenial |
Does not exist
|
|
linux-gke-5.4 Launchpad, Ubuntu, Debian |
bionic |
Not vulnerable
(5.4.0-1025.25~18.04.1)
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.8~rc1)
|
|
xenial |
Does not exist
|
|
linux-gkeop-5.4 Launchpad, Ubuntu, Debian |
bionic |
Not vulnerable
(5.4.0-1001.1)
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.8~rc1)
|
|
xenial |
Does not exist
|
|
linux-hwe-5.4 Launchpad, Ubuntu, Debian |
bionic |
Released
(5.4.0-45.49~18.04.2)
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.8~rc1)
|
|
xenial |
Does not exist
|
|
linux-hwe-5.8 Launchpad, Ubuntu, Debian |
bionic |
Does not exist
|
focal |
Not vulnerable
(5.8.0-23.24~20.04.1)
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.8~rc1)
|
|
xenial |
Does not exist
|
|
linux-hwe-edge Launchpad, Ubuntu, Debian |
bionic |
Ignored
(end of life, was needs-triage)
|
eoan |
Does not exist
|
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.8~rc1)
|
|
xenial |
Ignored
(end of life, was needs-triage)
|
|
linux-kvm Launchpad, Ubuntu, Debian |
bionic |
Released
(4.15.0-1072.73)
|
eoan |
Ignored
(end of life)
|
|
focal |
Released
(5.4.0-1021.21)
|
|
groovy |
Not vulnerable
(5.8.0-1001.1)
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.8~rc1)
|
|
xenial |
Released
(4.4.0-1077.84)
|
|
linux-lts-trusty Launchpad, Ubuntu, Debian |
bionic |
Does not exist
|
eoan |
Does not exist
|
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.8~rc1)
|
|
xenial |
Does not exist
|
|
linux-lts-xenial Launchpad, Ubuntu, Debian |
bionic |
Does not exist
|
eoan |
Does not exist
|
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Ignored
(was needs-triage ESM criteria)
|
|
upstream |
Released
(5.8~rc1)
|
|
xenial |
Does not exist
|
|
linux-oem Launchpad, Ubuntu, Debian |
bionic |
Released
(4.15.0-1094.104)
|
eoan |
Ignored
(end of life)
|
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.8~rc1)
|
|
xenial |
Ignored
(end of standard support, was needs-triage)
|
|
linux-oem-osp1 Launchpad, Ubuntu, Debian |
bionic |
Released
(5.0.0-1065.70)
|
eoan |
Ignored
(end of life)
|
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.8~rc1)
|
|
xenial |
Does not exist
|
|
linux-oracle Launchpad, Ubuntu, Debian |
bionic |
Released
(4.15.0-1051.55)
|
eoan |
Ignored
(end of life)
|
|
focal |
Released
(5.4.0-1022.22)
|
|
groovy |
Not vulnerable
(5.8.0-1001.1)
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.8~rc1)
|
|
xenial |
Released
(4.15.0-1051.55~16.04.1)
|
|
linux-oracle-5.0 Launchpad, Ubuntu, Debian |
bionic |
Ignored
(end of life, was needs-triage)
|
eoan |
Does not exist
|
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.8~rc1)
|
|
xenial |
Does not exist
|
|
linux-oracle-5.3 Launchpad, Ubuntu, Debian |
bionic |
Ignored
(end of life, was needs-triage)
|
eoan |
Does not exist
|
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.8~rc1)
|
|
xenial |
Does not exist
|
|
linux-oracle-5.4 Launchpad, Ubuntu, Debian |
bionic |
Released
(5.4.0-1022.22~18.04.1)
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.8~rc1)
|
|
xenial |
Does not exist
|
|
linux-raspi Launchpad, Ubuntu, Debian |
bionic |
Does not exist
|
eoan |
Does not exist
|
|
focal |
Released
(5.4.0-1016.17)
|
|
groovy |
Not vulnerable
(5.4.0-1016.17)
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.8~rc1)
|
|
xenial |
Does not exist
|
|
linux-raspi-5.4 Launchpad, Ubuntu, Debian |
bionic |
Released
(5.4.0-1016.17~18.04.1)
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.8~rc1)
|
|
xenial |
Does not exist
|
|
linux-raspi2 Launchpad, Ubuntu, Debian |
bionic |
Released
(4.15.0-1068.72)
|
eoan |
Ignored
(end of life)
|
|
focal |
Ignored
(end of life, was needs-triage)
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.8~rc1)
|
|
xenial |
Released
(4.4.0-1136.145)
|
|
linux-raspi2-5.3 Launchpad, Ubuntu, Debian |
bionic |
Released
(5.3.0-1030.32~18.04.2)
|
eoan |
Does not exist
|
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.8~rc1)
|
|
xenial |
Does not exist
|
|
linux-riscv Launchpad, Ubuntu, Debian |
bionic |
Does not exist
|
eoan |
Does not exist
|
|
focal |
Released
(5.4.0-31.35)
|
|
groovy |
Not vulnerable
(5.8.0-1.1)
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.8~rc1)
|
|
xenial |
Does not exist
|
|
linux-snapdragon Launchpad, Ubuntu, Debian |
bionic |
Released
(4.15.0-1084.92)
|
eoan |
Does not exist
|
|
focal |
Does not exist
|
|
groovy |
Does not exist
|
|
trusty |
Does not exist
|
|
upstream |
Released
(5.8~rc1)
|
|
xenial |
Released
(4.4.0-1140.148)
|
Severity score breakdown
Parameter | Value |
---|---|
Base score | 5.5 |
Attack vector | Local |
Attack complexity | Low |
Privileges required | Low |
User interaction | None |
Scope | Unchanged |
Confidentiality | None |
Integrity impact | None |
Availability impact | High |
Vector | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |