Advisory Published
Advisory Published

RHSA-2018:1638: Important: kernel security update

First published: Tue May 29 2018(Updated: )

The kernel packages contain the Linux kernel, the core of any Linux operating system.<br>Security Fix(es):<br><li> An industry-wide issue was found in the way many modern microprocessor designs have implemented speculative execution of Load &amp; Store instructions (a commonly used performance optimization). It relies on the presence of a precisely-defined instruction sequence in the privileged code as well as the fact that memory read from address to which a recent memory write has occurred may see an older value and subsequently cause an update into the microprocessor's data cache even for speculatively executed instructions that never actually commit (retire). As a result, an unprivileged attacker could use this flaw to read privileged memory by conducting targeted cache side-channel attacks. (CVE-2018-3639)</li> Note: This issue is present in hardware and cannot be fully fixed via software update. The updated kernel packages provide software side of the mitigation for this hardware issue. To be fully functional, up-to-date CPU microcode applied on the system is required. Please refer to References section for further information about this issue, CPU microcode requirements and the potential performance impact.<br>In this update mitigations for x86 (both 32 and 64 bit) architecture are provided.<br>Red Hat would like to thank Ken Johnson (Microsoft Security Response Center) and Jann Horn (Google Project Zero) for reporting this issue.

Affected SoftwareAffected VersionHow to fix
redhat/kernel<2.6.32-573.55.4.el6
2.6.32-573.55.4.el6
redhat/kernel<2.6.32-573.55.4.el6
2.6.32-573.55.4.el6
redhat/kernel-abi-whitelists<2.6.32-573.55.4.el6
2.6.32-573.55.4.el6
redhat/kernel-debug<2.6.32-573.55.4.el6
2.6.32-573.55.4.el6
redhat/kernel-debug-debuginfo<2.6.32-573.55.4.el6
2.6.32-573.55.4.el6
redhat/kernel-debug-debuginfo<2.6.32-573.55.4.el6
2.6.32-573.55.4.el6
redhat/kernel-debug-devel<2.6.32-573.55.4.el6
2.6.32-573.55.4.el6
redhat/kernel-debug-devel<2.6.32-573.55.4.el6
2.6.32-573.55.4.el6
redhat/kernel-debuginfo<2.6.32-573.55.4.el6
2.6.32-573.55.4.el6
redhat/kernel-debuginfo<2.6.32-573.55.4.el6
2.6.32-573.55.4.el6
redhat/kernel-debuginfo-common-i686<2.6.32-573.55.4.el6
2.6.32-573.55.4.el6
redhat/kernel-devel<2.6.32-573.55.4.el6
2.6.32-573.55.4.el6
redhat/kernel-doc<2.6.32-573.55.4.el6
2.6.32-573.55.4.el6
redhat/kernel-firmware<2.6.32-573.55.4.el6
2.6.32-573.55.4.el6
redhat/kernel-headers<2.6.32-573.55.4.el6
2.6.32-573.55.4.el6
redhat/perf<2.6.32-573.55.4.el6
2.6.32-573.55.4.el6
redhat/perf-debuginfo<2.6.32-573.55.4.el6
2.6.32-573.55.4.el6
redhat/perf-debuginfo<2.6.32-573.55.4.el6
2.6.32-573.55.4.el6
redhat/python-perf<2.6.32-573.55.4.el6
2.6.32-573.55.4.el6
redhat/python-perf-debuginfo<2.6.32-573.55.4.el6
2.6.32-573.55.4.el6
redhat/python-perf-debuginfo<2.6.32-573.55.4.el6
2.6.32-573.55.4.el6
redhat/kernel-debug<2.6.32-573.55.4.el6
2.6.32-573.55.4.el6
redhat/kernel-devel<2.6.32-573.55.4.el6
2.6.32-573.55.4.el6
redhat/kernel-headers<2.6.32-573.55.4.el6
2.6.32-573.55.4.el6
redhat/perf<2.6.32-573.55.4.el6
2.6.32-573.55.4.el6
redhat/python-perf<2.6.32-573.55.4.el6
2.6.32-573.55.4.el6
redhat/kernel-debuginfo-common-s390x<2.6.32-573.55.4.el6
2.6.32-573.55.4.el6
redhat/kernel-kdump<2.6.32-573.55.4.el6
2.6.32-573.55.4.el6
redhat/kernel-kdump-debuginfo<2.6.32-573.55.4.el6
2.6.32-573.55.4.el6
redhat/kernel-kdump-devel<2.6.32-573.55.4.el6
2.6.32-573.55.4.el6
redhat/kernel-bootwrapper<2.6.32-573.55.4.el6
2.6.32-573.55.4.el6
redhat/kernel-debuginfo-common-ppc64<2.6.32-573.55.4.el6
2.6.32-573.55.4.el6

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Frequently Asked Questions

  • What is the severity of RHSA-2018:1638?

    RHSA-2018:1638 is classified as a critical severity vulnerability due to its impact on the Linux kernel's speculative execution functionality.

  • How do I fix RHSA-2018:1638?

    To remediate RHSA-2018:1638, update kernel packages to version 2.6.32-573.55.4.el6 or later.

  • What systems are affected by RHSA-2018:1638?

    RHSA-2018:1638 affects systems running Red Hat Enterprise Linux 6 with the specified kernel package versions.

  • What are the potential risks of not addressing RHSA-2018:1638?

    Ignoring RHSA-2018:1638 may expose systems to exploits leveraging speculative execution vulnerabilities, leading to unauthorized access to sensitive data.

  • Is there a specific recommended action for RHSA-2018:1638?

    It is recommended to immediately apply the latest kernel updates provided by Red Hat to mitigate the risks associated with RHSA-2018:1638.

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