Synopsis
Important: kernel security, bug fix, and enhancement update
Type/Severity
Security Advisory: Important
Topic
An update for kernel is now available for Red Hat Enterprise Linux 7.4 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):
- A flaw named FragmentSmack was found in the way the Linux kernel handled reassembly of fragmented IPv4 and IPv6 packets. A remote attacker could use this flaw to trigger time and calculation expensive fragment reassembly algorithm by sending specially crafted packets which could lead to a CPU saturation and hence a denial of service on the system. (CVE-2018-5391)
- kernel: out-of-bounds access in the show_timer function in kernel/time/posix-timers.c (CVE-2017-18344)
- kernel: mm: use-after-free in do_get_mempolicy function allows local DoS or other unspecified impact (CVE-2018-10675)
- kernel: Integer overflow in Linux's create_elf_tables function (CVE-2018-14634)
For more details about the security issue(s), including the impact, a CVSS score, and other related information, refer to the CVE page(s) listed in the References section.
Red Hat would like to thank Juha-Matti Tilli (Aalto University - Department of Communications and Networking and Nokia Bell Labs) for reporting CVE-2018-5391 and Qualys Research Labs for reporting CVE-2018-14634.
Bug Fix(es):
These updated kernel packages include also numerous bug fixes. Space precludes documenting all of the bug fixes in this advisory. See the descriptions in the related Knowledge Article: https://access.redhat.com/articles/3684891
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 7.4 x86_64
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Red Hat Enterprise Linux for Power, big endian - Extended Update Support 7.4 ppc64
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Red Hat Enterprise Linux EUS Compute Node 7.4 x86_64
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Red Hat Enterprise Linux Server - AUS 7.4 x86_64
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Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 7.4 s390x
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Red Hat Enterprise Linux for Power, little endian - Extended Update Support 7.4 ppc64le
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Red Hat Enterprise Linux Server - TUS 7.4 x86_64
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Red Hat Enterprise Linux Server (for IBM Power LE) - Update Services for SAP Solutions 7.4 ppc64le
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Red Hat Enterprise Linux Server - Update Services for SAP Solutions 7.4 x86_64
Fixes
- BZ - 1575065 - CVE-2018-10675 kernel: mm: use-after-free in do_get_mempolicy function allows local DoS or other unspecified impact
- BZ - 1609664 - CVE-2018-5391 kernel: IP fragments with random offsets allow a remote denial of service (FragmentSmack)
- BZ - 1610958 - CVE-2017-18344 kernel: out-of-bounds access in the show_timer function in kernel/time/posix-timers.c
- BZ - 1624498 - CVE-2018-14634 kernel: Integer overflow in Linux's create_elf_tables function
CVEs
References
Vulmon