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Alerts This Week
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Red Hat Enterprise MRG 2: RHSA-2017:0932-01 Important Kernel-Rt Update

red hat
Calendar Grey April 12, 2017
Scroller Redhat
Debian releases new security patches for kernel-rt, categorizing vulnerabilities as critical; a series of enhancements boost operational reliability.
An update for kernel-rt is now available for Red Hat Enterprise MRG 2

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.

Summary

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)

References

https://access.redhat.com/security/cve/CVE-2016-8650 https://access.redhat.com/security/cve/CVE-2016-9793 https://access.redhat.com/security/cve/CVE-2017-2618 https://access.redhat.com/security/cve/CVE-2017-2636 https://access.redhat.com/security/cve/CVE-2017-6074 https://access.redhat.com/security/updates/classification/#important

Package List

MRG Realtime for RHEL 6 Server v.2:
Source: kernel-rt-3.10.0-514.rt56.219.el6rt.src.rpm
noarch: kernel-rt-doc-3.10.0-514.rt56.219.el6rt.noarch.rpm kernel-rt-firmware-3.10.0-514.rt56.219.el6rt.noarch.rpm
x86_64: kernel-rt-3.10.0-514.rt56.219.el6rt.x86_64.rpm kernel-rt-debug-3.10.0-514.rt56.219.el6rt.x86_64.rpm kernel-rt-debug-debuginfo-3.10.0-514.rt56.219.el6rt.x86_64.rpm kernel-rt-debug-devel-3.10.0-514.rt56.219.el6rt.x86_64.rpm kernel-rt-debuginfo-3.10.0-514.rt56.219.el6rt.x86_64.rpm kernel-rt-debuginfo-common-x86_64-3.10.0-514.rt56.219.el6rt.x86_64.rpm kernel-rt-devel-3.10.0-514.rt56.219.el6rt.x86_64.rpm kernel-rt-trace-3.10.0-514.rt56.219.el6rt.x86_64.rpm kernel-rt-trace-debuginfo-3.10.0-514.rt56.219.el6rt.x86_64.rpm kernel-rt-trace-devel-3.10.0-514.rt56.219.el6rt.x86_64.rpm kernel-rt-vanilla-3.10.0-514.rt56.219.el6rt.x86_64.rpm kernel-rt-vanilla-debuginfo-3.10.0-514.rt56.219.el6rt.x86_64.rpm kernel-rt-vanilla-devel-3.10.0-514.rt56.219.el6rt.x86_64.rpm
These packages are GPG signed by Red Hat for security. Our key and details on how to verify the signature are available from https://access.redhat.com/security/team/key/


Severity
important
Lowest
Low
Medium
High
Critical

Advisory ID: RHSA-2017:0932-01
Product: Red Hat Enterprise MRG for RHEL-6
Issue date: 2017-04-12

Topic

An update for kernel-rt is now available for Red Hat Enterprise MRG 2.Red Hat Product Security has rated this update as having a security impactof Important. A Common Vulnerability Scoring System (CVSS) base score,which gives a detailed severity rating, is available for each vulnerabilityfrom the CVE link(s) in the References section.

Relevant Releases Architectures

MRG Realtime for RHEL 6 Server v.2 - noarch, x86_64

Bugs Fixed

1395187 - CVE-2016-8650 kernel: Null pointer dereference via keyctl

1402013 - CVE-2016-9793 kernel: Signed overflow for SO_{SND|RCV}BUFFORCE

1419916 - CVE-2017-2618 kernel: Off-by-one error in selinux_setprocattr (/proc/self/attr/fscreate)

1423071 - CVE-2017-6074 kernel: use after free in dccp protocol

1428319 - CVE-2017-2636 kernel: Race condition access to n_hdlc.tbuf causes double free in n_hdlc_release()

1429613 - update the MRG 2.5.z 3.10 kernel-rt sources

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