RHEL 7 : kernel (RHSA-2018:2785)

high Nessus Plugin ID 117781
New! Plugin Severity Now Using CVSS v3

The calculated severity for Plugins has been updated to use CVSS v3 by default. Plugins that do not have a CVSS v3 score will fall back to CVSS v2 for calculating severity. Severity display preferences can be toggled in the settings dropdown.

Synopsis

The remote Red Hat host is missing one or more security updates.

Description

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.

The kernel packages contain the Linux kernel, the core of any Linux operating system.

Security Fix(es) :

* A flaw named SegmentSmack was found in the way the Linux kernel handled specially crafted TCP packets. A remote attacker could use this flaw to trigger time and calculation expensive calls to tcp_collapse_ofo_queue() and tcp_prune_ofo_queue() functions by sending specially modified packets within ongoing TCP sessions which could lead to a CPU saturation and hence a denial of service on the system. Maintaining the denial of service condition requires continuous two-way TCP sessions to a reachable open port, thus the attacks cannot be performed using spoofed IP addresses.
(CVE-2018-5390)

* 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: mm: use-after-free in do_get_mempolicy function allows local DoS or other unspecified impact (CVE-2018-10675)

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-2018-5390 and CVE-2018-5391.

Bug Fix(es) :

* On systems running Red Hat Enterprise Linux 7 with Red Hat OpenShift Container Platform 3.5, a node sometimes got into 'NodeNotReady' state after a CPU softlockup. Consequently, the node was not available. This update fixes an irq latency source in memory compaction. As a result, nodes no longer get into 'NodeNotReady' state under the described circumstances. (BZ#1596281)

* Previously, the kernel source code was missing support to report the Speculative Store Bypass Disable (SSBD) vulnerability status on IBM Power Systems and the little-endian variants of IBM Power Systems. As a consequence, the /sys/devices/system/cpu/vulnerabilities/spec_store_bypass file incorrectly reported 'Not affected' on both CPU architectures. This fix updates the kernel source code to properly report the SSBD status either as 'Vulnerable' or 'Mitigation: Kernel entry/exit barrier (TYPE)' where TYPE is one of 'eieio', 'hwsync', 'fallback', or 'unknown'. (BZ# 1612351)

* The hypervisors of Red Hat Enterprise Linux 7 virtual machines (VMs) in certain circumstances mishandled the microcode update in the kernel. As a consequence, the VMs sometimes became unresponsive when booting. This update applies an upstream patch to avoid early microcode update when running under a hypervisor. As a result, kernel hangs no longer occur in the described scenario. (BZ#1618388)

Solution

Update the affected packages.

See Also

https://access.redhat.com/errata/RHSA-2018:2785

https://access.redhat.com/security/cve/cve-2018-5390

https://access.redhat.com/security/cve/cve-2018-5391

https://access.redhat.com/security/cve/cve-2018-10675

Plugin Details

Severity: High

ID: 117781

File Name: redhat-RHSA-2018-2785.nasl

Version: 1.9

Type: local

Agent: unix

Published: 9/27/2018

Updated: 10/24/2019

Dependencies: ssh_get_info.nasl, linux_alt_patch_detect.nasl

Risk Information

VPR

Risk Factor: Medium

Score: 5.9

CVSS v2

Risk Factor: High

Base Score: 7.8

Vector: AV:N/AC:L/Au:N/C:N/I:N/A:C

CVSS v3

Risk Factor: High

Base Score: 7.8

Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Vulnerability Information

CPE: p-cpe:/a:redhat:enterprise_linux:kernel, p-cpe:/a:redhat:enterprise_linux:kernel-abi-whitelists, p-cpe:/a:redhat:enterprise_linux:kernel-debug, p-cpe:/a:redhat:enterprise_linux:kernel-debug-debuginfo, p-cpe:/a:redhat:enterprise_linux:kernel-debug-devel, p-cpe:/a:redhat:enterprise_linux:kernel-debuginfo, p-cpe:/a:redhat:enterprise_linux:kernel-debuginfo-common-s390x, p-cpe:/a:redhat:enterprise_linux:kernel-debuginfo-common-x86_64, p-cpe:/a:redhat:enterprise_linux:kernel-devel, p-cpe:/a:redhat:enterprise_linux:kernel-doc, p-cpe:/a:redhat:enterprise_linux:kernel-headers, p-cpe:/a:redhat:enterprise_linux:kernel-kdump, p-cpe:/a:redhat:enterprise_linux:kernel-kdump-debuginfo, p-cpe:/a:redhat:enterprise_linux:kernel-kdump-devel, p-cpe:/a:redhat:enterprise_linux:kernel-tools, p-cpe:/a:redhat:enterprise_linux:kernel-tools-debuginfo, p-cpe:/a:redhat:enterprise_linux:kernel-tools-libs, p-cpe:/a:redhat:enterprise_linux:kernel-tools-libs-devel, p-cpe:/a:redhat:enterprise_linux:perf, p-cpe:/a:redhat:enterprise_linux:perf-debuginfo, p-cpe:/a:redhat:enterprise_linux:python-perf, p-cpe:/a:redhat:enterprise_linux:python-perf-debuginfo, cpe:/o:redhat:enterprise_linux:7.3

Required KB Items: Host/local_checks_enabled, Host/RedHat/release, Host/RedHat/rpm-list, Host/cpu

Patch Publication Date: 9/25/2018

Vulnerability Publication Date: 5/2/2018

Reference Information

CVE: CVE-2018-10675, CVE-2018-5390, CVE-2018-5391

RHSA: 2018:2785