Synopsis
Important: kernel security and bug fix update
Type/Severity
Security Advisory: Important
Topic
An update for kernel is now available for Red Hat Enterprise Linux 7.3 Extended Update Support.
Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.
Description
The kernel packages contain the Linux kernel, the core of any Linux operating system.
Security Fix(es):
- An industry-wide issue was found in the way many modern microprocessor designs have implemented speculative execution of instructions (a commonly used performance optimization). There are three primary variants of the issue which differ in the way the speculative execution can be exploited. Variant CVE-2017-5754 relies on the fact that, on impacted microprocessors, during speculative execution of instruction permission faults, exception generation triggered by a faulting access is suppressed until the retirement of the whole instruction block. In a combination with the fact that memory accesses may populate the cache even when the block is being dropped and never committed (executed), an unprivileged local attacker could use this flaw to read privileged (kernel space) memory by conducting targeted cache side-channel attacks. (CVE-2017-5754, Important, KVM for Power)
Red Hat would like to thank Google Project Zero for reporting this issue.
Bug Fix(es):
These updated kernel packages include also numerous bug fixes. Space precludes documenting all of these bug fixes in this advisory. See the bug fix descriptions in the related Knowledge Article:
https://access.redhat.com/articles/3413511
Solution
For details on how to apply this update, which includes the changes described in this advisory, refer to:
https://access.redhat.com/articles/11258
The system must be rebooted for this update to take effect.
Affected Products
-
Red Hat Enterprise Linux Server - Extended Update Support 7.3 x86_64
-
Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 7.3 s390x
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Red Hat Enterprise Linux for Power, big endian - Extended Update Support 7.3 ppc64
-
Red Hat Enterprise Linux EUS Compute Node 7.3 x86_64
-
Red Hat Enterprise Linux Server - AUS 7.3 x86_64
-
Red Hat Enterprise Linux for Power, little endian - Extended Update Support 7.3 ppc64le
-
Red Hat Enterprise Linux Server - TUS 7.3 x86_64
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Red Hat Enterprise Linux Server (for IBM Power LE) - Update Services for SAP Solutions 7.3 ppc64le
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Red Hat Enterprise Linux Server - Update Services for SAP Solutions 7.3 x86_64
Fixes
- BZ - 1519781 - CVE-2017-5754 hw: cpu: speculative execution permission faults handling
CVEs
(none)
References
Vulmon