CVE-2020-10766

15.09.2020, 23:15

A logic bug flaw was found in Linux kernel before 5.8-rc1 in the implementation of SSBD. A bug in the logic handling allows an attacker with a local account to disable SSBD protection during a context switch when additional speculative execution mitigations are in place. This issue was introduced when the per task/process conditional STIPB switching was added on top of the existing SSBD switching. The highest threat from this vulnerability is to confidentiality.

Provider	Type	Base Score	Atk. Vector	Atk. Complexity	Priv. Required	Vector
NIST	NIST	5.5 MEDIUM	LOCAL	LOW	LOW	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
redhat	CNA	5.5 MEDIUM	LOCAL	LOW	LOW	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
CVE	ADP	---				---

Base Score

CVSS 3.x

EPSS Score

Percentile: 25%

Vendor	Product	Version
linux	linux_kernel	𝑥 < 5.8.0

𝑥

= Vulnerable software versions

Debian Releases

Debian Product

Codename

linux

bullseye	5.10.223-1 fixed
bullseye (security)	5.10.226-1 fixed
bookworm	6.1.106-3 fixed
bookworm (security)	6.1.112-1 fixed
trixie	6.11.5-1 fixed
sid	6.11.6-1 fixed

Ubuntu Releases

Ubuntu Product

Codename

linux

focal	Fixed 5.4.0-45.49 released
eoan	ignored
bionic	Fixed 4.15.0-115.116 released
xenial	Fixed 4.4.0-186.216 released
trusty	ignored

linux-aws

focal	Fixed 5.4.0-1022.22 released
eoan	ignored
bionic	Fixed 4.15.0-1080.84 released
xenial	Fixed 4.4.0-1111.123 released
trusty	Fixed 4.4.0-1075.79 released

linux-aws-5.0

focal	dne
eoan	dne
bionic	ignored
xenial	dne
trusty	dne

linux-aws-5.3

focal	dne
eoan	dne
bionic	Fixed 5.3.0-1032.34~18.04.2 released
xenial	dne
trusty	dne

linux-aws-5.4

focal	dne
bionic	Fixed 5.4.0-1022.22~18.04.1 released
xenial	dne
trusty	dne

linux-aws-hwe

focal	dne
eoan	dne
bionic	dne
xenial	Fixed 4.15.0-1080.84~16.04.1 released
trusty	dne

linux-azure

focal	Fixed 5.4.0-1023.23 released
eoan	ignored
bionic	ignored
xenial	Fixed 4.15.0-1093.103~16.04.1 released
trusty	Fixed 4.15.0-1093.103~14.04.1 released

linux-azure-4.15

focal	dne
eoan	dne
bionic	Fixed 4.15.0-1093.103 released
xenial	dne
trusty	dne

linux-azure-5.3

focal	dne
eoan	dne
bionic	Fixed 5.3.0-1034.35~18.04.1 released
xenial	dne
trusty	dne

linux-azure-5.4

focal	dne
bionic	Fixed 5.4.0-1023.23~18.04.1 released
xenial	dne
trusty	dne

linux-azure-edge

focal	dne
eoan	dne
bionic	ignored
xenial	dne
trusty	dne

linux-gcp

focal	Fixed 5.4.0-1022.22 released
eoan	ignored
bionic	ignored
xenial	Fixed 4.15.0-1081.92~16.04.1 released
trusty	dne

linux-gcp-4.15

focal	dne
eoan	dne
bionic	Fixed 4.15.0-1081.92 released
xenial	dne
trusty	dne

linux-gcp-5.3

focal	dne
eoan	dne
bionic	Fixed 5.3.0-1032.34~18.04.1 released
xenial	dne
trusty	dne

linux-gcp-5.4

focal	dne
bionic	Fixed 5.4.0-1022.22~18.04.1 released
xenial	dne
trusty	dne

linux-gcp-edge

focal	dne
eoan	dne
bionic	ignored
xenial	dne
trusty	dne

linux-gke-4.15

focal	dne
eoan	dne
bionic	Fixed 4.15.0-1067.70 released
xenial	dne
trusty	dne

linux-gke-5.0

focal	dne
eoan	dne
bionic	Fixed 5.0.0-1045.46 released
xenial	dne
trusty	dne

linux-gke-5.3

focal	dne
eoan	dne
bionic	Fixed 5.3.0-1032.34~18.04.1 released
xenial	dne
trusty	dne

linux-hwe

focal	dne
eoan	dne
bionic	Fixed 5.3.0-64.58~18.04.1 released
xenial	Fixed 4.15.0-115.116~16.04.1 released
trusty	dne

linux-hwe-5.4

focal	dne
bionic	Fixed 5.4.0-45.49~18.04.2 released
xenial	dne
trusty	dne

linux-hwe-edge

focal	dne
eoan	dne
bionic	ignored
xenial	ignored
trusty	dne

linux-kvm

focal	Fixed 5.4.0-1021.21 released
eoan	ignored
bionic	Fixed 4.15.0-1072.73 released
xenial	Fixed 4.4.0-1077.84 released
trusty	dne

linux-lts-trusty

focal	dne
eoan	dne
bionic	dne
xenial	dne
trusty	dne

linux-lts-xenial

focal	dne
eoan	dne
bionic	dne
xenial	dne
trusty	Fixed 4.4.0-186.216~14.04.1 released

linux-oem

focal	dne
eoan	ignored
bionic	Fixed 4.15.0-1094.104 released
xenial	ignored
trusty	dne

linux-oem-5.6

focal	Fixed 5.6.0-1020.20 released
eoan	dne
bionic	dne
xenial	dne
trusty	dne

linux-oem-osp1

focal	dne
eoan	ignored
bionic	Fixed 5.0.0-1065.70 released
xenial	dne
trusty	dne

linux-oracle

focal	Fixed 5.4.0-1022.22 released
eoan	ignored
bionic	Fixed 4.15.0-1051.55 released
xenial	Fixed 4.15.0-1051.55~16.04.1 released
trusty	dne

linux-oracle-5.0

focal	dne
eoan	dne
bionic	ignored
xenial	dne
trusty	dne

linux-oracle-5.3

focal	dne
eoan	dne
bionic	Fixed 5.3.0-1030.32~18.04.1 released
xenial	dne
trusty	dne

linux-oracle-5.4

focal	dne
bionic	Fixed 5.4.0-1022.22~18.04.1 released
xenial	dne
trusty	dne

linux-raspi

focal	Fixed 5.4.0-1016.17 released
eoan	dne
bionic	dne
xenial	dne
trusty	dne

linux-raspi-5.4

focal	dne
bionic	Fixed 5.4.0-1016.17~18.04.1 released
xenial	dne
trusty	dne

linux-raspi2

focal	ignored
eoan	ignored
bionic	Fixed 4.15.0-1068.72 released
xenial	Fixed 4.4.0-1136.145 released
trusty	dne

linux-raspi2-5.3

focal	dne
eoan	dne
bionic	Fixed 5.3.0-1030.32~18.04.2 released
xenial	dne
trusty	dne

linux-riscv

focal	Fixed 5.4.0-31.35 released
eoan	dne
bionic	dne
xenial	dne
trusty	dne

linux-snapdragon

focal	dne
eoan	dne
bionic	Fixed 4.15.0-1084.92 released
xenial	Fixed 4.4.0-1140.148 released
trusty	dne

Common Weakness Enumeration

CWE-440 - Expected Behavior Violation
A feature, API, or function does not perform according to its specification.

References

https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2020-10766

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=dbbe2ad02e9df26e372f38cc3e70dab9222c832e

https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2020-10766

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=dbbe2ad02e9df26e372f38cc3e70dab9222c832e