Race condition in Linux kernel - CVE-2020-10766

Vulnerability identifier: #VU47074

CSH Severity: Low

CVSS v4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N]

CVE-ID: CVE-2020-10766

CWE-ID: CWE-362

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local user to gain access to sensitive information.

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.

Linux kernel
Anolis OS
Red Hat Enterprise Linux for x86_64
Red Hat Enterprise Linux for Real Time for NFV
Red Hat Enterprise Linux for Real Time
Red Hat CodeReady Linux Builder for ARM 64
Red Hat CodeReady Linux Builder for Power, little endian
Red Hat CodeReady Linux Builder for x86_64
Red Hat Enterprise Linux for ARM 64
Red Hat Enterprise Linux for Power, little endian
Red Hat Enterprise Linux for IBM z Systems
Red Hat CodeReady Linux Builder for x86_64 - Extended Update Support
Red Hat CodeReady Linux Builder for Power, little endian - Extended Update Support
Red Hat CodeReady Linux Builder for ARM 64 - Extended Update Support
Red Hat Enterprise Linux for x86_64 - Extended Update Support
Red Hat Enterprise Linux for ARM 64 - Extended Update Support
Red Hat Enterprise Linux for Power, little endian - Extended Update Support
Red Hat Enterprise Linux for IBM z Systems - Extended Update Support
Red Hat Enterprise Linux Server - TUS
Red Hat Enterprise Linux Server - AUS
Ubuntu
Fedora
kpatch-patch-4_18_0-147_20_1 (Red Hat package)
kpatch-patch-4_18_0-193_6_3 (Red Hat package)
kpatch-patch-4_18_0-147_13_2 (Red Hat package)
kpatch-patch-4_18_0-193_1_2 (Red Hat package)
kpatch-patch-4_18_0-193 (Red Hat package)
kpatch-patch-4_18_0-147_8_1 (Red Hat package)
kpatch-patch-4_18_0-147_5_1 (Red Hat package)
kpatch-patch-4_18_0-147_0_2 (Red Hat package)
kpatch-patch-4_18_0-147_0_3 (Red Hat package)
kpatch-patch-4_18_0-147_3_1 (Red Hat package)
kpatch-patch-4_18_0-147 (Red Hat package)
linux-image-virtual (Ubuntu package)
linux-image-lowlatency (Ubuntu package)
linux-image-generic-lpae (Ubuntu package)
linux-image-generic (Ubuntu package)
linux-image-4.15.0-115-generic (Ubuntu package)
linux-image-4.15.0-115-generic-lpae (Ubuntu package)
linux-image-4.15.0-115-lowlatency (Ubuntu package)
linux-image-oracle (Ubuntu package)
linux-image-4.15.0-1051-oracle (Ubuntu package)
linux-image-oracle-lts-18.04 (Ubuntu package)
linux-image-4.15.0-1067-gke (Ubuntu package)
linux-image-gke (Ubuntu package)
linux-image-gke-4.15 (Ubuntu package)
linux-image-raspi2 (Ubuntu package)
linux-image-4.15.0-1068-raspi2 (Ubuntu package)
linux-image-kvm (Ubuntu package)
linux-image-4.15.0-1072-kvm (Ubuntu package)
linux-image-aws-hwe (Ubuntu package)
linux-image-aws-lts-18.04 (Ubuntu package)
linux-image-4.15.0-1080-aws (Ubuntu package)
linux-image-gcp (Ubuntu package)
linux-image-4.15.0-1081-gcp (Ubuntu package)
linux-image-gcp-lts-18.04 (Ubuntu package)
linux-image-snapdragon (Ubuntu package)
linux-image-4.15.0-1084-snapdragon (Ubuntu package)
linux-image-azure-lts-18.04 (Ubuntu package)
linux-image-azure (Ubuntu package)
linux-image-azure-edge (Ubuntu package)
linux-image-4.15.0-1093-azure (Ubuntu package)
linux-image-oem (Ubuntu package)
linux-image-4.15.0-1094-oem (Ubuntu package)
kernel (Red Hat package)
kernel-rt (Red Hat package)
bpftool
kernel-debug-devel
kernel
kernel-debug
kernel-devel
kernel-headers
kernel-tools
kernel-tools-libs
kernel-tools-libs-devel
perf
python-perf
linux-image-oem-osp1 (Ubuntu package)
linux-image-5.4.0-45-lowlatency (Ubuntu package)
linux-image-5.4.0-45-generic-lpae (Ubuntu package)
linux-image-5.4.0-45-generic (Ubuntu package)
linux-image-snapdragon-hwe-18.04 (Ubuntu package)
linux-image-virtual-hwe-18.04 (Ubuntu package)
linux-image-generic-hwe-18.04 (Ubuntu package)
linux-image-generic-lpae-hwe-18.04 (Ubuntu package)
linux-image-gkeop-5.4 (Ubuntu package)
linux-image-lowlatency-hwe-18.04 (Ubuntu package)
linux-image-5.4.0-1016-raspi (Ubuntu package)
linux-image-raspi-hwe-18.04 (Ubuntu package)
linux-image-raspi (Ubuntu package)
linux-image-aws-edge (Ubuntu package)
linux-image-gke-5.4 (Ubuntu package)
linux-image-5.4.0-1022-oracle (Ubuntu package)
linux-image-5.4.0-1022-gcp (Ubuntu package)
linux-image-5.4.0-1022-aws (Ubuntu package)
linux-image-aws (Ubuntu package)
linux-image-5.4.0-1023-azure (Ubuntu package)

Install update from vendor's website.

Linux kernel - update to 5.8.0
kpatch-patch-4_18_0-147_20_1 (Red Hat package) - update to 1-2.el8_1
kpatch-patch-4_18_0-193_6_3 (Red Hat package) - update to 1-2.el8_2
kpatch-patch-4_18_0-147_13_2 (Red Hat package) - update to 1-3.el8_1
kpatch-patch-4_18_0-193_1_2 (Red Hat package) - update to 1-3.el8_2
kpatch-patch-4_18_0-193 (Red Hat package) - update to 1-5.el8
kpatch-patch-4_18_0-147_8_1 (Red Hat package) - update to 1-5.el8_1
kpatch-patch-4_18_0-147_5_1 (Red Hat package) - update to 1-7.el8_1
kpatch-patch-4_18_0-147_0_2 (Red Hat package) - update to 1-12.el8
kpatch-patch-4_18_0-147_0_3 (Red Hat package) - update to 1-12.el8
kpatch-patch-4_18_0-147_3_1 (Red Hat package) - update to 1-12.el8_1
kpatch-patch-4_18_0-147 (Red Hat package) - update to 1-16.el8
linux-image-virtual (Ubuntu package) - addressed in versions 4.15.0.115.103, 5.4.0.45.49
linux-image-lowlatency (Ubuntu package) - addressed in versions 4.15.0.115.103, 5.4.0.45.49
linux-image-generic-lpae (Ubuntu package) - addressed in versions 4.15.0.115.103, 5.4.0.45.49
linux-image-generic (Ubuntu package) - addressed in versions 4.15.0.115.103, 5.4.0.45.49
linux-image-4.15.0-115-generic (Ubuntu package) - update to 4.15.0-115.116~16.04.1
linux-image-4.15.0-115-generic-lpae (Ubuntu package) - update to 4.15.0-115.116~16.04.1
linux-image-4.15.0-115-lowlatency (Ubuntu package) - update to 4.15.0-115.116~16.04.1
linux-image-oracle (Ubuntu package) - addressed in versions 4.15.0.1051.42, 5.4.0.1022.7, 5.4.0.1022.20
linux-image-4.15.0-1051-oracle (Ubuntu package) - addressed in versions 4.15.0-1051.55, 4.15.0-1051.55~16.04.1
linux-image-oracle-lts-18.04 (Ubuntu package) - update to 4.15.0.1051.62
linux-image-4.15.0-1067-gke (Ubuntu package) - update to 4.15.0-1067.70
linux-image-gke (Ubuntu package) - addressed in versions 4.15.0.1067.71, 4.15.0.1081.83, 5.4.0.1022.20
linux-image-gke-4.15 (Ubuntu package) - update to 4.15.0.1067.71
linux-image-raspi2 (Ubuntu package) - addressed in versions 4.15.0.1068.66, 5.4.0.1016.51
linux-image-4.15.0-1068-raspi2 (Ubuntu package) - update to 4.15.0-1068.72
linux-image-kvm (Ubuntu package) - addressed in versions 4.15.0.1072.68, 5.4.0.1021.20
linux-image-4.15.0-1072-kvm (Ubuntu package) - update to 4.15.0-1072.73
linux-image-aws-hwe (Ubuntu package) - update to 4.15.0.1080.77
linux-image-aws-lts-18.04 (Ubuntu package) - update to 4.15.0.1080.82
linux-image-4.15.0-1080-aws (Ubuntu package) - addressed in versions 4.15.0-1080.84, 4.15.0-1080.84~16.04.1
linux-image-gcp (Ubuntu package) - addressed in versions 4.15.0.1081.83, 5.4.0.1022.9, 5.4.0.1022.20
linux-image-4.15.0-1081-gcp (Ubuntu package) - addressed in versions 4.15.0-1081.92, 4.15.0-1081.92~16.04.1
linux-image-gcp-lts-18.04 (Ubuntu package) - update to 4.15.0.1081.99
linux-image-snapdragon (Ubuntu package) - update to 4.15.0.1084.87
linux-image-4.15.0-1084-snapdragon (Ubuntu package) - update to 4.15.0-1084.92
linux-image-azure-lts-18.04 (Ubuntu package) - update to 4.15.0.1093.67
linux-image-azure (Ubuntu package) - addressed in versions 4.15.0.1093.70, 4.15.0.1093.88, 5.4.0.1023.7, 5.4.0.1023.22
linux-image-azure-edge (Ubuntu package) - update to 4.15.0.1093.88
linux-image-4.15.0-1093-azure (Ubuntu package) - addressed in versions 4.15.0-1093.103, 4.15.0-1093.103~14.04.1, 4.15.0-1093.103~16.04.1
linux-image-oem (Ubuntu package) - addressed in versions 4.15.0.1094.98, 5.4.0.45.49
linux-image-4.15.0-1094-oem (Ubuntu package) - update to 4.15.0-1094.104
kernel (Red Hat package) - addressed in versions 4.18.0-80.27.1.el8_0, 4.18.0-147.24.2.el8_1, 4.18.0-193.13.2.el8_2
kernel-rt (Red Hat package) - update to 4.18.0-193.13.2.rt13.65.el8_2
bpftool - update to 4.19.91-26
kernel-debug-devel - update to 4.19.91-26
kernel - update to 4.19.91-26
kernel-debug - update to 4.19.91-26
kernel-devel - update to 4.19.91-26
kernel-headers - update to 4.19.91-26
kernel-tools - update to 4.19.91-26
kernel-tools-libs - update to 4.19.91-26
kernel-tools-libs-devel - update to 4.19.91-26
perf - update to 4.19.91-26
python-perf - update to 4.19.91-26
linux-image-oem-osp1 (Ubuntu package) - update to 5.4.0.45.49
linux-image-5.4.0-45-lowlatency (Ubuntu package) - update to 5.4.0-45.49~18.04.2
linux-image-5.4.0-45-generic-lpae (Ubuntu package) - update to 5.4.0-45.49~18.04.2
linux-image-5.4.0-45-generic (Ubuntu package) - update to 5.4.0-45.49~18.04.2
linux-image-snapdragon-hwe-18.04 (Ubuntu package) - update to 5.4.0.45.49~18.04.38
linux-image-virtual-hwe-18.04 (Ubuntu package) - update to 5.4.0.45.49~18.04.38
linux-image-generic-hwe-18.04 (Ubuntu package) - update to 5.4.0.45.49~18.04.38
linux-image-generic-lpae-hwe-18.04 (Ubuntu package) - update to 5.4.0.45.49~18.04.38
linux-image-gkeop-5.4 (Ubuntu package) - update to 5.4.0.45.49~18.04.38
linux-image-lowlatency-hwe-18.04 (Ubuntu package) - update to 5.4.0.45.49~18.04.38
linux-image-5.4.0-1016-raspi (Ubuntu package) - update to 5.4.0-1016.17~18.04.1
linux-image-raspi-hwe-18.04 (Ubuntu package) - update to 5.4.0.1016.20
linux-image-raspi (Ubuntu package) - update to 5.4.0.1016.51
linux-image-aws-edge (Ubuntu package) - update to 5.4.0.1022.8
linux-image-gke-5.4 (Ubuntu package) - update to 5.4.0.1022.9
linux-image-5.4.0-1022-oracle (Ubuntu package) - update to 5.4.0-1022.22~18.04.1
linux-image-5.4.0-1022-gcp (Ubuntu package) - update to 5.4.0-1022.22~18.04.1
linux-image-5.4.0-1022-aws (Ubuntu package) - update to 5.4.0-1022.22~18.04.1
linux-image-aws (Ubuntu package) - update to 5.4.0.1022.23
linux-image-5.4.0-1023-azure (Ubuntu package) - update to 5.4.0-1023.23~18.04.1
kernel - addressed in versions 5.6.19-200.fc31, 5.6.19-300.fc32

• 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

• Information disclosure in Linux kernel
• Red Hat Enterprise Linux 8 update for kernel
• Red Hat Enterprise Linux 8 update for kernel-rt
• Red Hat Enterprise Linux 8.0 Update Services for SAP Solutions update for kernel
• Red Hat Enterprise Linux 8 update for kpatch-patch
• Red Hat Enterprise Linux 8.1 Extended Update Support update for kernel
• Red Hat Enterprise Linux 8.1 Extended Update Support update for kpatch-patch
• Anolis OS update for kernel(ANCK)4.19
• Ubuntu update for linux
• Ubuntu update for linux
• Fedora 32 update for kernel
• Fedora 31 update for kernel