RHEL 6 : kernel-rt (RHSA-2017:0932)

high Nessus Plugin ID 99345

Synopsis

The remote Red Hat host is missing one or more security updates for kernel-rt.

Description

The remote Redhat Enterprise Linux 6 host has packages installed that are affected by multiple vulnerabilities as referenced in the RHSA-2017:0932 advisory.

The kernel-rt packages provide the Real Time Linux Kernel, which enables fine-tuning for systems with extremely high determinism requirements.

Security Fix(es):

* A race condition flaw was found in the N_HLDC Linux kernel driver when accessing n_hdlc.tbuf list that can lead to double free. A local, unprivileged user able to set the HDLC line discipline on the tty device could use this flaw to increase their privileges on the system. (CVE-2017-2636, Important)

* A use-after-free flaw was found in the way the Linux kernel's Datagram Congestion Control Protocol (DCCP) implementation freed SKB (socket buffer) resources for a DCCP_PKT_REQUEST packet when the IPV6_RECVPKTINFO option is set on the socket. A local, unprivileged user could use this flaw to alter the kernel memory, allowing them to escalate their privileges on the system. (CVE-2017-6074, Important)

* A flaw was found in the Linux kernel key management subsystem in which a local attacker could crash the kernel or corrupt the stack and additional memory (denial of service) by supplying a specially crafted RSA key. This flaw panics the machine during the verification of the RSA key. (CVE-2016-8650, Moderate)

* A flaw was found in the Linux kernel's implementation of setsockopt for the SO_{SND|RCV}BUFFORCE setsockopt() system call. Users with non-namespace CAP_NET_ADMIN are able to trigger this call and create a situation in which the sockets sendbuff data size could be negative. This could adversely affect memory allocations and create situations where the system could crash or cause memory corruption. (CVE-2016-9793, Moderate)

* A flaw was found in the Linux kernel's handling of clearing SELinux attributes on /proc/pid/attr files.
An empty (null) write to this file can crash the system by causing the system to attempt to access unmapped kernel memory. (CVE-2017-2618, Moderate)

Red Hat would like to thank Alexander Popov for reporting CVE-2017-2636; Andrey Konovalov (Google) for reporting CVE-2017-6074; and Ralf Spenneberg for reporting CVE-2016-8650. The CVE-2017-2618 issue was discovered by Paul Moore (Red Hat Engineering).

Bug Fix(es):

* The kernel-rt packages have been upgraded to version 3.10.0-514.rt56.219, which provides a number of bug fix updates over the previous version. (BZ#1429613)

Tenable has extracted the preceding description block directly from the Red Hat Enterprise Linux security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

Solution

Update the RHEL kernel-rt package based on the guidance in RHSA-2017:0932.

See Also

http://www.nessus.org/u?d02d8c40

https://access.redhat.com/errata/RHSA-2017:0932

https://access.redhat.com/security/updates/classification/#important

https://bugzilla.redhat.com/show_bug.cgi?id=1395187

https://bugzilla.redhat.com/show_bug.cgi?id=1402013

https://bugzilla.redhat.com/show_bug.cgi?id=1419916

https://bugzilla.redhat.com/show_bug.cgi?id=1423071

https://bugzilla.redhat.com/show_bug.cgi?id=1428319

https://bugzilla.redhat.com/show_bug.cgi?id=1429613

Plugin Details

Severity: High

ID: 99345

File Name: redhat-RHSA-2017-0932.nasl

Version: 3.15

Type: local

Agent: unix

Published: 4/13/2017

Updated: 3/24/2025

Supported Sensors: Frictionless Assessment AWS, Frictionless Assessment Azure, Frictionless Assessment Agent, Nessus Agent, Agentless Assessment, Continuous Assessment, Nessus

Risk Information

VPR

Risk Factor: Critical

Score: 9.2

Vendor

Vendor Severity: Important

CVSS v2

Risk Factor: High

Base Score: 7.2

Temporal Score: 6.3

Vector: CVSS2#AV:L/AC:L/Au:N/C:C/I:C/A:C

CVSS Score Source: CVE-2017-6074

CVSS v3

Risk Factor: High

Base Score: 7.8

Temporal Score: 7.5

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

Temporal Vector: CVSS:3.0/E:H/RL:O/RC:C

Vulnerability Information

CPE: p-cpe:/a:redhat:enterprise_linux:kernel-rt, p-cpe:/a:redhat:enterprise_linux:kernel-rt-debug-devel, p-cpe:/a:redhat:enterprise_linux:kernel-rt-devel, cpe:/o:redhat:enterprise_linux:6, p-cpe:/a:redhat:enterprise_linux:kernel-rt-trace-devel, p-cpe:/a:redhat:enterprise_linux:kernel-rt-vanilla-devel, p-cpe:/a:redhat:enterprise_linux:kernel-rt-firmware, p-cpe:/a:redhat:enterprise_linux:kernel-rt-trace, p-cpe:/a:redhat:enterprise_linux:kernel-rt-debug, p-cpe:/a:redhat:enterprise_linux:kernel-rt-doc, p-cpe:/a:redhat:enterprise_linux:kernel-rt-vanilla

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

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 4/12/2017

Vulnerability Publication Date: 11/28/2016

Exploitable With

Core Impact

Reference Information

CVE: CVE-2016-8650, CVE-2016-9793, CVE-2017-2618, CVE-2017-2636, CVE-2017-6074

CWE: 190, 193, 362, 416, 476

RHSA: 2017:0932