Amazon Linux 2 Security Advisory: ALASKERNEL-5.4-2022-013
Advisory Release Date: 2022-01-20 19:22 Pacific
Advisory Updated Date: 2022-01-28 17:22 Pacific
FAQs regarding Amazon Linux ALAS/CVE Severity
A logic bug flaw was found in the Linux kernel's 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. The highest threat from this vulnerability is to confidentiality. (CVE-2020-10766)
A flaw was found in the Linux kernel's implementation of the Enhanced IBPB (Indirect Branch Prediction Barrier). The IBPB mitigation will be disabled when STIBP is not available or when the Enhanced Indirect Branch Restricted Speculation (IBRS) is available. This flaw allows a local attacker to perform a Spectre V2 style attack when this configuration is active. The highest threat from this vulnerability is to confidentiality. (CVE-2020-10767)
A flaw was found in the prctl() function, where it can be used to enable indirect branch speculation after it has been disabled. This call incorrectly reports it as being 'force disabled' when it is not and opens the system to Spectre v2 attacks. The highest threat from this vulnerability is to confidentiality. (CVE-2020-10768)
An issue was discovered in the Linux kernel through 5.6.11. btree_gc_coalesce in drivers/md/bcache/btree.c has a deadlock if a coalescing operation fails. (CVE-2020-12771)
Affected Packages:
kernel
Note:
This advisory is applicable to Amazon Linux 2 - Kernel-5.4 Extra. Visit this page to learn more about Amazon Linux 2 (AL2) Extras and this FAQ section for the difference between AL2 Core and AL2 Extras advisories.
Issue Correction:
Run yum update kernel to update your system.
aarch64:
kernel-5.4.50-25.83.amzn2.aarch64
kernel-headers-5.4.50-25.83.amzn2.aarch64
kernel-debuginfo-common-aarch64-5.4.50-25.83.amzn2.aarch64
perf-5.4.50-25.83.amzn2.aarch64
perf-debuginfo-5.4.50-25.83.amzn2.aarch64
python-perf-5.4.50-25.83.amzn2.aarch64
python-perf-debuginfo-5.4.50-25.83.amzn2.aarch64
kernel-tools-5.4.50-25.83.amzn2.aarch64
kernel-tools-devel-5.4.50-25.83.amzn2.aarch64
kernel-tools-debuginfo-5.4.50-25.83.amzn2.aarch64
kernel-devel-5.4.50-25.83.amzn2.aarch64
kernel-debuginfo-5.4.50-25.83.amzn2.aarch64
i686:
kernel-headers-5.4.50-25.83.amzn2.i686
src:
kernel-5.4.50-25.83.amzn2.src
x86_64:
kernel-5.4.50-25.83.amzn2.x86_64
kernel-headers-5.4.50-25.83.amzn2.x86_64
kernel-debuginfo-common-x86_64-5.4.50-25.83.amzn2.x86_64
perf-5.4.50-25.83.amzn2.x86_64
perf-debuginfo-5.4.50-25.83.amzn2.x86_64
python-perf-5.4.50-25.83.amzn2.x86_64
python-perf-debuginfo-5.4.50-25.83.amzn2.x86_64
kernel-tools-5.4.50-25.83.amzn2.x86_64
kernel-tools-devel-5.4.50-25.83.amzn2.x86_64
kernel-tools-debuginfo-5.4.50-25.83.amzn2.x86_64
kernel-devel-5.4.50-25.83.amzn2.x86_64
kernel-debuginfo-5.4.50-25.83.amzn2.x86_64