1. Ubuntu Security Notices
  2. USN-4883-1

USN-4883-1: Linux kernel vulnerabilities

Publication date

29 March 2021

Overview

Several security issues were fixed in the Linux kernel.

Releases

Packages

  • linux - Linux kernel
  • linux-aws - Linux kernel for Amazon Web Services (AWS) systems
  • linux-aws-hwe - Linux kernel for Amazon Web Services (AWS-HWE) systems
  • linux-azure - Linux kernel for Microsoft Azure Cloud systems
  • linux-azure-4.15 - Linux kernel for Microsoft Azure Cloud systems
  • linux-gcp - Linux kernel for Google Cloud Platform (GCP) systems
  • linux-gcp-4.15 - Linux kernel for Google Cloud Platform (GCP) systems
  • linux-hwe - Linux hardware enablement (HWE) kernel
  • linux-kvm - Linux kernel for cloud environments
  • linux-oracle - Linux kernel for Oracle Cloud systems
  • linux-raspi2 - Linux kernel for Raspberry Pi (V8) systems
  • linux-snapdragon - Linux kernel for Qualcomm Snapdragon processors

Details

Adam Nichols discovered that heap overflows existed in the iSCSI subsystem
in the Linux kernel. A local attacker could use this to cause a denial of
service (system crash) or possibly execute arbitrary code. (CVE-2021-27365)

Adam Nichols discovered that the iSCSI subsystem in the Linux kernel did
not properly restrict access to iSCSI transport handles. A local attacker
could use this to cause a denial of service or expose sensitive information
(kernel pointer addresses). (CVE-2021-27363)

Adam Nichols discovered that an out-of-bounds read existed in the iSCSI
subsystem in the Linux kernel. A local attacker could use this to cause a
denial of service (system crash) or expose sensitive information (kernel
memory). (CVE-2021-27364)

Adam Nichols discovered that heap overflows existed in the iSCSI subsystem
in the Linux kernel. A local attacker could use this to cause a denial of
service (system crash) or possibly execute arbitrary code. (CVE-2021-27365)

Adam Nichols discovered that the iSCSI subsystem in the Linux kernel did
not properly restrict access to iSCSI transport handles. A local attacker
could use this to cause a denial of service or expose sensitive information
(kernel pointer addresses). (CVE-2021-27363)

Adam Nichols discovered that an out-of-bounds read existed in the iSCSI
subsystem in the Linux kernel. A local attacker could use this to cause a
denial of service (system crash) or expose sensitive information (kernel
memory). (CVE-2021-27364)

Update instructions

After a standard system update you need to reboot your computer to make all the necessary changes.

Learn more about how to get the fixes.

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.

The problem can be corrected by updating your system to the following package versions:

Ubuntu Release Package Version
18.04 bionic linux-image-4.15.0-1081-raspi2 –  4.15.0-1081.86
linux-image-4.15.0-139-lowlatency –  4.15.0-139.143
linux-image-gcp-lts-18.04 –  4.15.0.1095.113
linux-image-4.15.0-1087-kvm –  4.15.0-1087.89
linux-image-oracle-lts-18.04 –  4.15.0.1067.77
linux-image-4.15.0-1095-gcp –  4.15.0-1095.108
linux-image-virtual –  4.15.0.139.126
linux-image-snapdragon –  4.15.0.1098.101
linux-image-4.15.0-139-generic –  4.15.0-139.143
linux-image-4.15.0-139-generic-lpae –  4.15.0-139.143
linux-image-4.15.0-1096-aws –  4.15.0-1096.103
linux-image-aws-lts-18.04 –  4.15.0.1096.99
linux-image-4.15.0-1110-azure –  4.15.0-1110.122
linux-image-generic –  4.15.0.139.126
linux-image-4.15.0-1098-snapdragon –  4.15.0-1098.107
linux-image-kvm –  4.15.0.1087.83
linux-image-raspi2 –  4.15.0.1081.78
linux-image-azure-lts-18.04 –  4.15.0.1110.83
linux-image-generic-lpae –  4.15.0.139.126
linux-image-4.15.0-1067-oracle –  4.15.0-1067.75
linux-image-lowlatency –  4.15.0.139.126
16.04 xenial linux-image-4.15.0-1067-oracle –  4.15.0-1067.75~16.04.1
linux-image-4.4.0-206-powerpc-smp –  4.4.0-206.238
linux-image-4.4.0-1152-snapdragon –  4.4.0-1152.162
linux-image-4.4.0-206-powerpc-e500mc –  4.4.0-206.238
linux-image-4.15.0-1096-aws –  4.15.0-1096.103~16.04.1
linux-image-powerpc-e500mc –  4.4.0.206.212
linux-image-generic-hwe-16.04 –  4.15.0.139.134
linux-image-4.15.0-139-lowlatency –  4.15.0-139.143~16.04.1
linux-image-virtual-hwe-16.04 –  4.15.0.139.134
linux-image-oracle –  4.15.0.1067.55
linux-image-azure –  4.15.0.1110.101
linux-image-generic-lpae-hwe-16.04 –  4.15.0.139.134
linux-image-4.4.0-1090-kvm –  4.4.0-1090.99
linux-image-4.15.0-1095-gcp –  4.15.0-1095.108~16.04.1
linux-image-virtual –  4.4.0.206.212
linux-image-aws-hwe –  4.15.0.1096.89
linux-image-4.15.0-139-generic-lpae –  4.15.0-139.143~16.04.1
linux-image-4.4.0-206-generic-lpae –  4.4.0-206.238
linux-image-4.4.0-206-powerpc64-smp –  4.4.0-206.238
linux-image-4.15.0-139-generic –  4.15.0-139.143~16.04.1
linux-image-aws –  4.4.0.1124.129
linux-image-4.4.0-206-lowlatency –  4.4.0-206.238
linux-image-gke –  4.15.0.1095.96
linux-image-azure-edge –  4.15.0.1110.101
linux-image-4.15.0-1110-azure –  4.15.0-1110.122~16.04.1
linux-image-generic –  4.4.0.206.212
linux-image-4.4.0-1124-aws –  4.4.0-1124.138
linux-image-4.4.0-1148-raspi2 –  4.4.0-1148.158
linux-image-oem –  4.15.0.139.134
linux-image-kvm –  4.4.0.1090.88
linux-image-raspi2 –  4.4.0.1148.148
linux-image-snapdragon –  4.4.0.1152.144
linux-image-powerpc-smp –  4.4.0.206.212
linux-image-generic-lpae –  4.4.0.206.212
linux-image-4.4.0-206-powerpc64-emb –  4.4.0-206.238
linux-image-gcp –  4.15.0.1095.96
linux-image-lowlatency-hwe-16.04 –  4.15.0.139.134
linux-image-powerpc64-emb –  4.4.0.206.212
linux-image-4.4.0-206-generic –  4.4.0-206.238
linux-image-powerpc64-smp –  4.4.0.206.212
linux-image-lowlatency –  4.4.0.206.212
14.04 trusty linux-image-4.15.0-1110-azure –  4.15.0-1110.122~14.04.1
linux-image-aws –  4.4.0.1088.85
linux-image-4.4.0-1088-aws –  4.4.0-1088.92
linux-image-azure –  4.15.0.1110.83

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References

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