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AUSCERT External Security Bulletin Redistribution
ESB-2020.4284
USN-4660-1: Linux kernel vulnerabilities
4 December 2020
===========================================================================
AusCERT Security Bulletin Summary
---------------------------------
Product: Linux Kernel
Publisher: Ubuntu
Operating System: Ubuntu
Impact/Access: Execute Arbitrary Code/Commands -- Existing Account
Increased Privileges -- Existing Account
Denial of Service -- Existing Account
Access Privileged Data -- Existing Account
Access Confidential Data -- Existing Account
Unauthorised Access -- Existing Account
Reduced Security -- Existing Account
Resolution: Patch/Upgrade
CVE Names: CVE-2020-28915 CVE-2020-25645 CVE-2020-25643
CVE-2020-25641 CVE-2020-25285 CVE-2020-25284
CVE-2020-25211 CVE-2020-14390 CVE-2020-14351
CVE-2020-4788
Reference: ESB-2020.4168
ESB-2020.4059
ESB-2020.3936
Original Bulletin:
https://ubuntu.com/security/notices/USN-4660-1
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USN-4660-1: Linux kernel vulnerabilities
03 December 2020
Several security issues were fixed in the Linux kernel.
Releases
o Ubuntu 18.04 LTS
o Ubuntu 16.04 LTS
o Ubuntu 14.04 ESM
Packages
o linux - Linux kernel
o linux-aws - Linux kernel for Amazon Web Services (AWS) systems
o linux-aws-hwe - Linux kernel for Amazon Web Services (AWS-HWE) systems
o linux-azure - Linux kernel for Microsoft Azure Cloud systems
o linux-azure-4.15 - Linux kernel for Microsoft Azure Cloud systems
o linux-gcp - Linux kernel for Google Cloud Platform (GCP) systems
o linux-gcp-4.15 - Linux kernel for Google Cloud Platform (GCP) systems
o linux-gke-4.15 - Linux kernel for Google Container Engine (GKE) systems
o linux-hwe - Linux hardware enablement (HWE) kernel
o linux-kvm - Linux kernel for cloud environments
o linux-oem - Linux kernel for OEM systems
o linux-oracle - Linux kernel for Oracle Cloud systems
o linux-raspi2 - Linux kernel for Raspberry Pi (V8) systems
o linux-snapdragon - Linux kernel for Qualcomm Snapdragon processors
Details
It was discovered that a race condition existed in the perf subsystem of
the Linux kernel, leading to a use-after-free vulnerability. An attacker
with access to the perf subsystem could use this to cause a denial of
service (system crash) or possibly execute arbitrary code. (CVE-2020-14351)
It was discovered that the frame buffer implementation in the Linux kernel
did not properly handle some edge cases in software scrollback. A local
attacker could use this to cause a denial of service (system crash) or
possibly execute arbitrary code. (CVE-2020-14390)
It was discovered that the netfilter connection tracker for netlink in the
Linux kernel did not properly perform bounds checking in some situations. A
local attacker could use this to cause a denial of service (system crash).
(CVE-2020-25211)
It was discovered that the Rados block device (rbd) driver in the Linux
kernel did not properly perform privilege checks for access to rbd devices
in some situations. A local attacker could use this to map or unmap rbd
block devices. (CVE-2020-25284)
It was discovered that a race condition existed in the hugetlb sysctl
implementation in the Linux kernel. A privileged attacker could use this to
cause a denial of service (system crash). (CVE-2020-25285)
It was discovered that the block layer subsystem in the Linux kernel did
not properly handle zero-length requests. A local attacker could use this
to cause a denial of service. (CVE-2020-25641)
It was discovered that the HDLC PPP implementation in the Linux kernel did
not properly validate input in some situations. A local attacker could use
this to cause a denial of service (system crash) or possibly execute
arbitrary code. (CVE-2020-25643)
It was discovered that the GENEVE tunnel implementation in the Linux kernel
when combined with IPSec did not properly select IP routes in some
situations. An attacker could use this to expose sensitive information
(unencrypted network traffic). (CVE-2020-25645)
It was discovered that the framebuffer implementation in the Linux kernel
did not properly perform range checks in certain situations. A local
attacker could use this to expose sensitive information (kernel memory).
(CVE-2020-28915)
It was discovered that Power 9 processors could be coerced to expose
information from the L1 cache in certain situations. A local attacker could
use this to expose sensitive information. (CVE-2020-4788)
Update instructions
The problem can be corrected by updating your system to the following package
versions:
Ubuntu 18.04
o linux-image-4.15.0-1059-oracle - 4.15.0-1059.65
o linux-image-4.15.0-1074-gke - 4.15.0-1074.79
o linux-image-4.15.0-1074-raspi2 - 4.15.0-1074.79
o linux-image-4.15.0-1079-kvm - 4.15.0-1079.81
o linux-image-4.15.0-1088-aws - 4.15.0-1088.93
o linux-image-4.15.0-1088-gcp - 4.15.0-1088.101
o linux-image-4.15.0-1091-snapdragon - 4.15.0-1091.100
o linux-image-4.15.0-1100-azure - 4.15.0-1100.111
o linux-image-4.15.0-1103-oem - 4.15.0-1103.114
o linux-image-4.15.0-126-generic - 4.15.0-126.129
o linux-image-4.15.0-126-generic-lpae - 4.15.0-126.129
o linux-image-4.15.0-126-lowlatency - 4.15.0-126.129
o linux-image-aws-lts-18.04 - 4.15.0.1088.90
o linux-image-azure-lts-18.04 - 4.15.0.1100.73
o linux-image-gcp-lts-18.04 - 4.15.0.1088.106
o linux-image-generic - 4.15.0.126.113
o linux-image-generic-lpae - 4.15.0.126.113
o linux-image-gke - 4.15.0.1074.78
o linux-image-gke-4.15 - 4.15.0.1074.78
o linux-image-kvm - 4.15.0.1079.75
o linux-image-lowlatency - 4.15.0.126.113
o linux-image-oem - 4.15.0.1103.107
o linux-image-oracle-lts-18.04 - 4.15.0.1059.69
o linux-image-powerpc-e500mc - 4.15.0.126.113
o linux-image-powerpc-smp - 4.15.0.126.113
o linux-image-powerpc64-emb - 4.15.0.126.113
o linux-image-powerpc64-smp - 4.15.0.126.113
o linux-image-raspi2 - 4.15.0.1074.71
o linux-image-snapdragon - 4.15.0.1091.94
o linux-image-virtual - 4.15.0.126.113
Ubuntu 16.04
o linux-image-4.15.0-1059-oracle - 4.15.0-1059.65~16.04.1
o linux-image-4.15.0-1088-aws - 4.15.0-1088.93~16.04.1
o linux-image-4.15.0-1088-gcp - 4.15.0-1088.101~16.04.1
o linux-image-4.15.0-1100-azure - 4.15.0-1100.111~16.04.1
o linux-image-4.15.0-126-generic - 4.15.0-126.129~16.04.1
o linux-image-4.15.0-126-generic-lpae - 4.15.0-126.129~16.04.1
o linux-image-4.15.0-126-lowlatency - 4.15.0-126.129~16.04.1
o linux-image-aws-hwe - 4.15.0.1088.82
o linux-image-azure - 4.15.0.1100.93
o linux-image-azure-edge - 4.15.0.1100.93
o linux-image-gcp - 4.15.0.1088.89
o linux-image-generic-hwe-16.04 - 4.15.0.126.125
o linux-image-generic-lpae-hwe-16.04 - 4.15.0.126.125
o linux-image-gke - 4.15.0.1088.89
o linux-image-lowlatency-hwe-16.04 - 4.15.0.126.125
o linux-image-oem - 4.15.0.126.125
o linux-image-oracle - 4.15.0.1059.48
o linux-image-virtual-hwe-16.04 - 4.15.0.126.125
Ubuntu 14.04
o linux-image-4.15.0-1100-azure - 4.15.0-1100.111~14.04.1
o linux-image-azure - 4.15.0.1100.75
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
o CVE-2020-14351
o CVE-2020-25643
o CVE-2020-25284
o CVE-2020-25285
o CVE-2020-25645
o CVE-2020-28915
o CVE-2020-4788
o CVE-2020-25211
o CVE-2020-14390
o CVE-2020-25641
Related notices
o USN-4576-1 : linux-image-raspi2, linux-image-raspi, linux-gcp,
linux-image-virtual-hwe-18.04, linux-image-5.4.0-51-generic, linux-hwe-5.4,
linux-raspi-5.4, linux-image-azure, linux-image-kvm,
linux-image-generic-lpae, linux-image-oracle, linux-image-oem-osp1,
linux-image-generic-lpae-hwe-20.04, linux-image-5.4.0-1021-raspi,
linux-image-generic-hwe-18.04, linux-image-5.4.0-51-lowlatency,
linux-image-generic-lpae-hwe-18.04, linux-image-aws, linux-image-gke,
linux-image-5.4.0-1026-kvm, linux-image-gcp, linux-oracle,
linux-image-lowlatency-hwe-18.04, linux-image-lowlatency,
linux-image-generic, linux-image-raspi-hwe-18.04, linux,
linux-image-lowlatency-hwe-20.04, linux-raspi, linux-image-5.4.0-1028-aws,
linux-aws-5.4, linux-image-generic-hwe-20.04,
linux-image-snapdragon-hwe-18.04, linux-image-5.4.0-1028-gcp,
linux-image-oem, linux-azure, linux-oracle-5.4, linux-image-virtual,
linux-kvm, linux-image-5.4.0-51-generic-lpae, linux-image-5.4.0-1031-azure,
linux-gcp-5.4, linux-aws, linux-image-5.4.0-1028-oracle,
linux-image-virtual-hwe-20.04, linux-azure-5.4
o USN-4579-1 : linux-image-raspi2, linux-image-4.4.0-1081-aws,
linux-lts-xenial, linux-image-kvm, linux-image-generic-lpae,
linux-snapdragon, linux-image-lowlatency-lts-xenial,
linux-image-4.4.0-193-powerpc-smp, linux-image-powerpc64-smp,
linux-image-4.4.0-1082-kvm, linux-image-4.4.0-193-generic-lpae,
linux-image-4.4.0-1145-snapdragon, linux-image-aws,
linux-image-4.4.0-1117-aws, linux-image-powerpc-smp,
linux-image-4.4.0-193-generic, linux-image-4.4.0-193-powerpc64-smp,
linux-image-lowlatency, linux-image-4.4.0-193-powerpc64-emb,
linux-image-generic, linux, linux-image-4.4.0-193-lowlatency,
linux-image-powerpc-e500mc, linux-image-4.4.0-1141-raspi2,
linux-image-powerpc64-emb, linux-image-snapdragon,
linux-image-generic-lpae-lts-xenial, linux-image-virtual, linux-kvm,
linux-raspi2, linux-aws, linux-image-4.4.0-193-powerpc-e500mc,
linux-image-virtual-lts-xenial, linux-image-generic-lts-xenial
o USN-4657-1 : linux-image-raspi2, linux-lts-xenial,
linux-image-4.4.0-197-powerpc-smp, linux-image-kvm,
linux-image-generic-lpae, linux-snapdragon,
linux-image-powerpc-e500mc-lts-xenial, linux-image-4.4.0-197-lowlatency,
linux-image-4.4.0-1142-raspi2, linux-image-4.4.0-197-powerpc-e500mc,
linux-image-4.4.0-1146-snapdragon, linux-image-4.4.0-197-powerpc64-emb,
linux-image-4.4.0-197-generic, linux-image-powerpc64-smp-lts-xenial,
linux-image-powerpc64-smp, linux-image-powerpc64-emb-lts-xenial,
linux-image-aws, linux-image-4.4.0-197-generic-lpae,
linux-image-powerpc-smp, linux-image-powerpc-smp-lts-xenial,
linux-image-4.4.0-197-powerpc64-smp, linux-image-lowlatency,
linux-image-generic, linux, linux-image-powerpc-e500mc,
linux-image-powerpc64-emb, linux-image-snapdragon,
linux-image-generic-lpae-lts-xenial, linux-image-4.4.0-1118-aws,
linux-image-4.4.0-1084-kvm, linux-image-4.4.0-1082-aws,
linux-image-virtual, linux-kvm, linux-raspi2, linux-aws,
linux-image-lowlatency-lts-xenial, linux-image-virtual-lts-xenial,
linux-image-generic-lts-xenial
o USN-4658-1 : linux-gcp, linux-image-virtual-hwe-18.04, linux-hwe-5.4,
linux-image-azure, linux-image-5.4.0-1028-kvm, linux-image-kvm,
linux-image-generic-lpae, linux-image-oracle, linux-image-oem-osp1,
linux-image-5.4.0-56-generic-lpae, linux-image-generic-lpae-hwe-20.04,
linux-image-5.4.0-1030-aws, linux-image-generic-hwe-18.04,
linux-image-5.4.0-1030-oracle, linux-image-generic-lpae-hwe-18.04,
linux-image-aws, linux-image-gke, linux-image-5.4.0-56-lowlatency,
linux-image-gcp, linux-oracle, linux-image-lowlatency-hwe-18.04,
linux-image-lowlatency, linux-image-generic, linux-image-5.4.0-1030-gcp,
linux, linux-image-lowlatency-hwe-20.04, linux-image-5.4.0-1032-azure,
linux-aws-5.4, linux-image-generic-hwe-20.04,
linux-image-snapdragon-hwe-18.04, linux-image-oem, linux-azure,
linux-oracle-5.4, linux-image-virtual, linux-kvm,
linux-image-5.4.0-56-generic, linux-gcp-5.4, linux-aws,
linux-image-virtual-hwe-20.04, linux-azure-5.4
o USN-4659-1 : linux-image-raspi, linux-gcp, linux-image-azure,
linux-image-kvm, linux-image-generic-lpae, linux-image-5.8.0-31-generic,
linux-image-oem-20.04, linux-image-oracle,
linux-image-5.8.0-31-generic-64k, linux-image-5.8.0-1008-raspi-nolpae,
linux-image-5.8.0-1008-raspi, linux-image-5.8.0-1011-kvm,
linux-image-5.8.0-31-generic-lpae, linux-image-raspi-nolpae,
linux-image-5.8.0-1013-azure, linux-image-5.8.0-31-lowlatency,
linux-image-aws, linux-image-gke, linux-image-generic-64k, linux-image-gcp,
linux-oracle, linux-image-lowlatency, linux-image-generic, linux-raspi,
linux, linux-image-5.8.0-1012-gcp, linux-azure,
linux-image-5.8.0-1011-oracle, linux-image-virtual, linux-kvm,
linux-image-5.8.0-1014-aws, linux-aws
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