USN-5091-1: Linux kernel vulnerabilities
=========================================================================
Ubuntu Security Notice USN-5091-1
September 28, 2021
linux, linux-aws, linux-aws-5.4, linux-azure, linux-azure-5.4, linux-gcp,
linux-gcp-5.4, linux-gke, linux-gke-5.4, linux-gkeop, linux-gkeop-5.4,
linux-hwe-5.4, linux-kvm, linux-oracle, linux-oracle-5.4 vulnerabilities
=========================================================================
A security issue affects these releases of Ubuntu and its derivatives:
- Ubuntu 20.04 LTS
- Ubuntu 18.04 LTS
Summary:
Several security issues were fixed in the Linux kernel.
Software Description:
- linux: Linux kernel
- linux-aws: Linux kernel for Amazon Web Services (AWS) systems
- linux-azure: Linux kernel for Microsoft Azure Cloud systems
- linux-gcp: Linux kernel for Google Cloud Platform (GCP) systems
- linux-gke: Linux kernel for Google Container Engine (GKE) systems
- linux-gkeop: Linux kernel for Google Container Engine (GKE) systems
- linux-kvm: Linux kernel for cloud environments
- linux-oracle: Linux kernel for Oracle Cloud systems
- linux-aws-5.4: Linux kernel for Amazon Web Services (AWS) systems
- linux-azure-5.4: Linux kernel for Microsoft Azure cloud systems
- linux-gcp-5.4: Linux kernel for Google Cloud Platform (GCP) systems
- linux-gke-5.4: Linux kernel for Google Container Engine (GKE) systems
- linux-gkeop-5.4: Linux kernel for Google Container Engine (GKE) systems
- linux-hwe-5.4: Linux hardware enablement (HWE) kernel
- linux-oracle-5.4: Linux kernel for Oracle Cloud systems
Details:
Ofek Kirzner, Adam Morrison, Benedict Schlueter, and Piotr Krysiuk
discovered that the BPF verifier in the Linux kernel missed possible
mispredicted branches due to type confusion, allowing a side-channel
attack. An attacker could use this to expose sensitive information.
(CVE-2021-33624)
It was discovered that the tracing subsystem in the Linux kernel did not
properly keep track of per-cpu ring buffer state. A privileged attacker
could use this to cause a denial of service. (CVE-2021-3679)
Alexey Kardashevskiy discovered that the KVM implementation for PowerPC
systems in the Linux kernel did not properly validate RTAS arguments in
some situations. An attacker in a guest vm could use this to cause a denial
of service (host OS crash) or possibly execute arbitrary code.
(CVE-2021-37576)
It was discovered that the Virtio console implementation in the Linux
kernel did not properly validate input lengths in some situations. A local
attacker could possibly use this to cause a denial of service (system
crash). (CVE-2021-38160)
Michael Wakabayashi discovered that the NVSv4 client implementation in the
Linux kernel did not properly order connection setup operations. An
attacker controlling a remote NFS server could use this to cause a denial
of service on the client. (CVE-2021-38199)
It was discovered that the MAX-3421 host USB device driver in the Linux
kernel did not properly handle device removal events. A physically
proximate attacker could use this to cause a denial of service (system
crash). (CVE-2021-38204)
Update instructions:
The problem can be corrected by updating your system to the following
package versions:
Ubuntu 20.04 LTS:
linux-image-5.4.0-1024-gkeop 5.4.0-1024.25
linux-image-5.4.0-1047-kvm 5.4.0-1047.49
linux-image-5.4.0-1053-gcp 5.4.0-1053.57
linux-image-5.4.0-1053-gke 5.4.0-1053.56
linux-image-5.4.0-1055-oracle 5.4.0-1055.59
linux-image-5.4.0-1057-aws 5.4.0-1057.60
linux-image-5.4.0-1059-azure 5.4.0-1059.62
linux-image-5.4.0-88-generic 5.4.0-88.99
linux-image-5.4.0-88-generic-lpae 5.4.0-88.99
linux-image-5.4.0-88-lowlatency 5.4.0-88.99
linux-image-aws-lts-20.04 5.4.0.1057.60
linux-image-azure-lts-20.04 5.4.0.1059.57
linux-image-gcp-lts-20.04 5.4.0.1053.63
linux-image-generic 5.4.0.88.92
linux-image-generic-lpae 5.4.0.88.92
linux-image-gke 5.4.0.1053.63
linux-image-gke-5.4 5.4.0.1053.63
linux-image-gkeop 5.4.0.1024.27
linux-image-gkeop-5.4 5.4.0.1024.27
linux-image-kvm 5.4.0.1047.46
linux-image-lowlatency 5.4.0.88.92
linux-image-oem 5.4.0.88.92
linux-image-oem-osp1 5.4.0.88.92
linux-image-oracle-lts-20.04 5.4.0.1055.55
linux-image-virtual 5.4.0.88.92
Ubuntu 18.04 LTS:
linux-image-5.4.0-1024-gkeop 5.4.0-1024.25~18.04.1
linux-image-5.4.0-1053-gcp 5.4.0-1053.57~18.04.1
linux-image-5.4.0-1053-gke 5.4.0-1053.56~18.04.1
linux-image-5.4.0-1055-oracle 5.4.0-1055.59~18.04.1
linux-image-5.4.0-1057-aws 5.4.0-1057.60~18.04.1
linux-image-5.4.0-1059-azure 5.4.0-1059.62~18.04.1
linux-image-5.4.0-87-generic 5.4.0-87.98~18.04.1
linux-image-5.4.0-87-generic-lpae 5.4.0-87.98~18.04.1
linux-image-5.4.0-87-lowlatency 5.4.0-87.98~18.04.1
linux-image-aws 5.4.0.1057.40
linux-image-azure 5.4.0.1059.39
linux-image-gcp 5.4.0.1053.39
linux-image-generic-hwe-18.04 5.4.0.87.98~18.04.78
linux-image-generic-lpae-hwe-18.04 5.4.0.87.98~18.04.78
linux-image-gke-5.4 5.4.0.1053.56~18.04.18
linux-image-gkeop-5.4 5.4.0.1024.25~18.04.25
linux-image-lowlatency-hwe-18.04 5.4.0.87.98~18.04.78
linux-image-oem 5.4.0.87.98~18.04.78
linux-image-oem-osp1 5.4.0.87.98~18.04.78
linux-image-oracle 5.4.0.1055.59~18.04.35
linux-image-snapdragon-hwe-18.04 5.4.0.87.98~18.04.78
linux-image-virtual-hwe-18.04 5.4.0.87.98~18.04.78
After a standard system update you need to reboot your computer to make
all the necessary changes.
ATTENTION: Due to an unavoidable ABI change the kernel updates have
been given a new version number, which requires you to recompile and
reinstall all third party kernel modules you might have installed.
Unless you manually uninstalled the standard kernel metapackages
(e.g. linux-generic, linux-generic-lts-RELEASE, linux-virtual,
linux-powerpc), a standard system upgrade will automatically perform
this as well.
References:
https://ubuntu.com/security/notices/USN-5091-1
CVE-2021-33624, CVE-2021-3679, CVE-2021-37576, CVE-2021-38160,
CVE-2021-38199, CVE-2021-38204
Package Information:
https://launchpad.net/ubuntu/+source/linux/5.4.0-88.99
https://launchpad.net/ubuntu/+source/linux-aws/5.4.0-1057.60
https://launchpad.net/ubuntu/+source/linux-azure/5.4.0-1059.62
https://launchpad.net/ubuntu/+source/linux-gcp/5.4.0-1053.57
https://launchpad.net/ubuntu/+source/linux-gke/5.4.0-1053.56
https://launchpad.net/ubuntu/+source/linux-gkeop/5.4.0-1024.25
https://launchpad.net/ubuntu/+source/linux-kvm/5.4.0-1047.49
https://launchpad.net/ubuntu/+source/linux-oracle/5.4.0-1055.59
https://launchpad.net/ubuntu/+source/linux-aws-5.4/5.4.0-1057.60~18.04.1
https://launchpad.net/ubuntu/+source/linux-azure-5.4/5.4.0-1059.62~18.04.1
https://launchpad.net/ubuntu/+source/linux-gcp-5.4/5.4.0-1053.57~18.04.1
https://launchpad.net/ubuntu/+source/linux-gke-5.4/5.4.0-1053.56~18.04.1
https://launchpad.net/ubuntu/+source/linux-gkeop-5.4/5.4.0-1024.25~18.04.1
https://launchpad.net/ubuntu/+source/linux-hwe-5.4/5.4.0-87.98~18.04.1
https://launchpad.net/ubuntu/+source/linux-oracle-5.4/5.4.0-1055.59~18.04.1
A Linux kernel security update has been released for Ubuntu Linux 18.04 LTS and 20.04 LTS.
