Improper Initialization in Linux kernel - CVE-2021-20317

Vulnerability identifier: #VU58208

CSH Severity: Low

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

CVE-ID: CVE-2021-20317

CWE-ID: CWE-665

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local user to perform a denial of service (DoS) attack.

The vulnerability exists due to improper initialization the Linux kernel. A corrupted timer tree causes the task wakeup to be missing in the timerqueue_add function in lib/timerqueue.c. A local user can run a specially crafted application to crash the kernel.

Linux kernel
Debian Linux
Anolis OS
Red Hat Enterprise Linux for IBM z Systems
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 x86_64
Red Hat Enterprise Linux Server - TUS
Red Hat Enterprise Linux Server - AUS
Red Hat Enterprise Linux for x86_64 - Extended Update Support
Red Hat Enterprise Linux for IBM z Systems - Extended Update Support
Red Hat Enterprise Linux for Power, little endian - Extended Update Support
Red Hat Enterprise Linux for ARM 64 - Extended Update Support
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
Ubuntu
openEuler
kernel-rt (Red Hat package)
kernel (Red Hat package)
Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions
Red Hat Enterprise Linux Server for x86_64 - Update Services for SAP Solutions
linux-image-lowlatency (Ubuntu package)
linux-image-virtual (Ubuntu package)
linux-image-generic-lpae (Ubuntu package)
linux-image-generic (Ubuntu package)
linux-image-4.15.0-166-lowlatency (Ubuntu package)
linux-image-4.15.0-166-generic-lpae (Ubuntu package)
linux-image-4.15.0-166-generic (Ubuntu package)
linux-image-virtual-hwe-16.04 (Ubuntu package)
linux-image-lowlatency-hwe-16.04 (Ubuntu package)
linux-image-generic-hwe-16.04 (Ubuntu package)
linux-image-dell300x (Ubuntu package)
linux-image-4.15.0-1033-dell300x (Ubuntu package)
linux-image-4.15.0-1085-oracle (Ubuntu package)
linux-image-oracle-lts-18.04 (Ubuntu package)
linux-image-aws-hwe (Ubuntu package)
linux-image-raspi2 (Ubuntu package)
linux-image-4.15.0-1101-raspi2 (Ubuntu package)
linux-image-kvm (Ubuntu package)
linux-image-4.15.0-1105-kvm (Ubuntu package)
linux-image-4.15.0-1114-gcp (Ubuntu package)
linux-image-gcp-lts-18.04 (Ubuntu package)
linux-image-snapdragon (Ubuntu package)
linux-image-aws-lts-18.04 (Ubuntu package)
linux-image-4.15.0-1118-aws (Ubuntu package)
linux-image-4.15.0-1118-snapdragon (Ubuntu package)
linux-image-azure-lts-18.04 (Ubuntu package)
linux-image-4.15.0-1129-azure (Ubuntu package)
kernel-doc
kernel-tools
kernel-tools-libs
bpftool
kernel
perf
kernel-core
python3-perf
kernel-cross-headers
kernel-debug
kernel-abi-whitelists
kernel-debug-core
kernel-debug-devel
kernel-debug-modules
kernel-debug-modules-extra
kernel-devel
kernel-headers
kernel-modules
kernel-modules-extra
kernel-tools-devel
kernel-tools-debuginfo
bpftool-debuginfo
python3-perf-debuginfo
python2-perf
kernel-debugsource
kernel-debuginfo
kernel-source
python2-perf-debuginfo
perf-debuginfo
kernel-modules-internal
kernel-tools-libs-devel
python-perf
linux (Debian package)
linux-image-oem (Ubuntu package)
linux-image-oracle (Ubuntu package)
linux-image-azure (Ubuntu package)
linux-image-gke (Ubuntu package)
linux-image-gcp (Ubuntu package)
SCALANCE LPE9403
Red Hat Advanced Cluster Management for Kubernetes

Install updates from vendor's website.

Linux kernel - update to 5.4
kernel-rt (Red Hat package) - addressed in versions 4.18.0-193.70.1.rt13.120.el8_2, 4.18.0-305.28.1.rt7.100.el8_4, 4.18.0-348.2.1.rt7.132.el8_5
kernel (Red Hat package) - addressed in versions 4.18.0-193.70.1.el8_2, 4.18.0-305.28.1.el8_4, 4.18.0-348.2.1.el8_5
SCALANCE LPE9403 - update to 2.0
Red Hat Advanced Cluster Management for Kubernetes - update to 2.2.10
linux-image-lowlatency (Ubuntu package) - update to 4.15.0.166.155
linux-image-virtual (Ubuntu package) - update to 4.15.0.166.155
linux-image-generic-lpae (Ubuntu package) - update to 4.15.0.166.155
linux-image-generic (Ubuntu package) - update to 4.15.0.166.155
linux-image-4.15.0-166-lowlatency (Ubuntu package) - update to 4.15.0-166.174
linux-image-4.15.0-166-generic-lpae (Ubuntu package) - update to 4.15.0-166.174
linux-image-4.15.0-166-generic (Ubuntu package) - update to 4.15.0-166.174
linux-image-virtual-hwe-16.04 (Ubuntu package) - update to 4.15.0.187.173
linux-image-lowlatency-hwe-16.04 (Ubuntu package) - update to 4.15.0.187.173
linux-image-generic-hwe-16.04 (Ubuntu package) - update to 4.15.0.187.173
linux-image-dell300x (Ubuntu package) - update to 4.15.0.1033.35
linux-image-4.15.0-1033-dell300x (Ubuntu package) - update to 4.15.0-1033.38
linux-image-4.15.0-1085-oracle (Ubuntu package) - update to 4.15.0-1085.93
linux-image-oracle-lts-18.04 (Ubuntu package) - update to 4.15.0.1085.95
linux-image-aws-hwe (Ubuntu package) - update to 4.15.0.1099.92
linux-image-raspi2 (Ubuntu package) - update to 4.15.0.1101.99
linux-image-4.15.0-1101-raspi2 (Ubuntu package) - update to 4.15.0-1101.108
linux-image-kvm (Ubuntu package) - update to 4.15.0.1105.101
linux-image-4.15.0-1105-kvm (Ubuntu package) - update to 4.15.0-1105.107
linux-image-4.15.0-1114-gcp (Ubuntu package) - update to 4.15.0-1114.128
linux-image-gcp-lts-18.04 (Ubuntu package) - update to 4.15.0.1114.133
linux-image-snapdragon (Ubuntu package) - update to 4.15.0.1118.121
linux-image-aws-lts-18.04 (Ubuntu package) - update to 4.15.0.1118.121
linux-image-4.15.0-1118-aws (Ubuntu package) - update to 4.15.0-1118.125
linux-image-4.15.0-1118-snapdragon (Ubuntu package) - update to 4.15.0-1118.127
linux-image-azure-lts-18.04 (Ubuntu package) - update to 4.15.0.1129.102
linux-image-4.15.0-1129-azure (Ubuntu package) - update to 4.15.0-1129.142
kernel-doc - addressed in versions 4.18.0-193.70.1, 4.18.0-305.28.1
kernel-tools - addressed in versions 4.18.0-193.70.1, 4.18.0-305.28.1, 4.19.91-25.6, 4.19.91-26
kernel-tools-libs - addressed in versions 4.18.0-193.70.1, 4.18.0-305.28.1, 4.19.91-25.6, 4.19.91-26
bpftool - addressed in versions 4.18.0-193.70.1, 4.18.0-305.28.1, 4.19.91-25.6, 4.19.91-26
kernel - addressed in versions 4.18.0-193.70.1, 4.18.0-305.28.1, 4.19.91-25.6, 4.19.91-26
perf - addressed in versions 4.18.0-193.70.1, 4.18.0-305.28.1, 4.19.91-25.6, 4.19.91-26
kernel-core - addressed in versions 4.18.0-193.70.1, 4.18.0-305.28.1, 4.19.91-25.6
python3-perf - addressed in versions 4.18.0-193.70.1, 4.18.0-305.28.1, 4.19.91-25.6
kernel-cross-headers - addressed in versions 4.18.0-193.70.1, 4.18.0-305.28.1
kernel-debug - addressed in versions 4.18.0-193.70.1, 4.18.0-305.28.1, 4.19.91-25.6, 4.19.91-26
kernel-abi-whitelists - update to 4.18.0-193.70.1
kernel-debug-core - addressed in versions 4.18.0-193.70.1, 4.18.0-305.28.1, 4.19.91-25.6
kernel-debug-devel - addressed in versions 4.18.0-193.70.1, 4.18.0-305.28.1, 4.19.91-25.6, 4.19.91-26
kernel-debug-modules - addressed in versions 4.18.0-193.70.1, 4.18.0-305.28.1, 4.19.91-25.6
kernel-debug-modules-extra - addressed in versions 4.18.0-193.70.1, 4.18.0-305.28.1, 4.19.91-25.6
kernel-devel - addressed in versions 4.18.0-193.70.1, 4.18.0-305.28.1, 4.19.91-25.6, 4.19.91-26
kernel-headers - addressed in versions 4.18.0-193.70.1, 4.18.0-305.28.1, 4.19.91-25.6, 4.19.91-26
kernel-modules - addressed in versions 4.18.0-193.70.1, 4.18.0-305.28.1, 4.19.91-25.6
kernel-modules-extra - addressed in versions 4.18.0-193.70.1, 4.18.0-305.28.1, 4.19.91-25.6
kernel-tools-devel - update to 4.19.90-2110.3.0.0116
kernel-tools - update to 4.19.90-2110.3.0.0116
kernel - update to 4.19.90-2110.3.0.0116
kernel-devel - update to 4.19.90-2110.3.0.0116
kernel-tools-debuginfo - update to 4.19.90-2110.3.0.0116
bpftool - update to 4.19.90-2110.3.0.0116
bpftool-debuginfo - update to 4.19.90-2110.3.0.0116
python3-perf-debuginfo - update to 4.19.90-2110.3.0.0116
python2-perf - update to 4.19.90-2110.3.0.0116
perf - update to 4.19.90-2110.3.0.0116
kernel-debugsource - update to 4.19.90-2110.3.0.0116
python3-perf - update to 4.19.90-2110.3.0.0116
kernel-debuginfo - update to 4.19.90-2110.3.0.0116
kernel-source - update to 4.19.90-2110.3.0.0116
python2-perf-debuginfo - update to 4.19.90-2110.3.0.0116
perf-debuginfo - update to 4.19.90-2110.3.0.0116
kernel-modules-internal - update to 4.19.91-25.6
kernel-tools-libs-devel - addressed in versions 4.19.91-25.6, 4.19.91-26
python-perf - update to 4.19.91-26
linux (Debian package) - update to 4.19.232-1
linux-image-oem (Ubuntu package) - update to 5.4.0.91.95
linux-image-oracle (Ubuntu package) - update to 5.11.0.1022.23~20.04.15
linux-image-azure (Ubuntu package) - update to 5.11.0.1022.23~20.04.22
linux-image-gke (Ubuntu package) - update to 5.11.0.1023.23
linux-image-gcp (Ubuntu package) - update to 5.11.0.1023.25~20.04.22

• https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/commit/?id=511885d7061eda3eb1faf3f57dcc936ff75863f1
• https://bugzilla.redhat.com/show_bug.cgi?id=2005258

• Denial of service in Linux kernel timer queue implementation
• Red Hat Enterprise Linux 8.4 update for kernel
• Red Hat Enterprise Linux for Real Time 8.4 update for kernel-rt
• Red Hat Enterprise Linux 8 update for kernel
• Red Hat Enterprise Linux 8 update for kernel-rt
• Red Hat Enterprise Linux for Real Time 8.2 update for kernel-rt
• Red Hat Enterprise Linux 8.2 update for kernel
• Debian update for linux 4.19
• Multiple vulnerabilities in Siemens SCALANCE LPE9403
• Ubuntu update for linux
• Debian update for linux
• openEuler update for kernel
• Anolis OS update for kernel(RHCK)4.18 (Anolis OS 8.2)
• Anolis OS update for kernel(RHCK)4.18
• Anolis OS update for kernel(ANCK)4.19
• Multiple vulnerabilities in Red Hat Advanced Cluster Management for Kubernetes 2.2
• Anolis OS update for kernel