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Red Hat Enterprise Linux 6.6 RHSA-2016:1640-01 Important Memory Escalation

red hat
Calendar Grey August 19, 2016
Scroller Redhat
A significant kernel upgrade for CentOS Stream targets vulnerabilities and enhances stability. Discover more information here.
An update for kernel is now available for Red Hat Enterprise Linux 6.6 Extended Update Support

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 packages contain the Linux kernel, the core of any Linux operating system.
Security Fix(es):
* A flaw was found in the way certain interfaces of the Linux kernel's Infiniband subsystem used write() as bi-directional ioctl() replacement, which could lead to insufficient memory security checks when being invoked using the splice() system call. A local unprivileged user on a system with either Infiniband hardware present or RDMA Userspace Connection Manager Access module explicitly loaded, could use this flaw to escalate their privileges on the system. (CVE-2016-4565, Important)
Red Hat would like to thank Jann Horn for reporting this issue.
Bug Fix(es):
* After upgrading the kernel, the CPU load average was higher compared to the prior kernel version due to the modification of the scheduler. The provided patchset rolls back the calculation algorithm of the load average to the status of the previous system version, thus resulting in lower values in the same system load. (BZ#1343013)

Topics%20covered

Topics Covered

security advisory Red Hat Enterprise Linux important kernel escalation memory

References

https://access.redhat.com/security/cve/CVE-2016-4565 https://access.redhat.com/security/updates/classification/#important

Package List

Red Hat Enterprise Linux HPC Node EUS (v. 6.6):
Source: kernel-2.6.32-504.51.1.el6.src.rpm
noarch: kernel-abi-whitelists-2.6.32-504.51.1.el6.noarch.rpm kernel-doc-2.6.32-504.51.1.el6.noarch.rpm kernel-firmware-2.6.32-504.51.1.el6.noarch.rpm
x86_64: kernel-2.6.32-504.51.1.el6.x86_64.rpm kernel-debug-2.6.32-504.51.1.el6.x86_64.rpm kernel-debug-debuginfo-2.6.32-504.51.1.el6.i686.rpm kernel-debug-debuginfo-2.6.32-504.51.1.el6.x86_64.rpm kernel-debug-devel-2.6.32-504.51.1.el6.i686.rpm kernel-debug-devel-2.6.32-504.51.1.el6.x86_64.rpm kernel-debuginfo-2.6.32-504.51.1.el6.i686.rpm kernel-debuginfo-2.6.32-504.51.1.el6.x86_64.rpm kernel-debuginfo-common-i686-2.6.32-504.51.1.el6.i686.rpm kernel-debuginfo-common-x86_64-2.6.32-504.51.1.el6.x86_64.rpm kernel-devel-2.6.32-504.51.1.el6.x86_64.rpm kernel-headers-2.6.32-504.51.1.el6.x86_64.rpm perf-2.6.32-504.51.1.el6.x86_64.rpm perf-debuginfo-2.6.32-504.51.1.el6.i686.rpm perf-debuginfo-2.6.32-504.51.1.el6.x86_64.rpm python-perf-debuginfo-2.6.32-504.51.1.el6.i686.rpm python-perf-debuginfo-2.6.32-504.51.1.el6.x86_64.rpm
Red Hat Enterprise Linux HPC Node Optional EUS (v. 6.6):
x86_64: kernel-debug-debuginfo-2.6.32-504.51.1.el6.x86_64.rpm kernel-debuginfo-2.6.32-504.51.1.el6.x86_64.rpm

Read the Full Advisory


Severity
important
Lowest
Low
Medium
High
Critical

Advisory ID: RHSA-2016:1640-01
Product: Red Hat Enterprise Linux
Advisory URL: https://access.redhat.com/errata/RHSA-2016:1640.html
Issue date: 2016-08-19

Topic

An update for kernel is now available for Red Hat Enterprise Linux 6.6Extended Update Support.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.

Topics%20covered

Topics Covered

security advisory Red Hat Enterprise Linux important kernel escalation memory

Relevant Releases Architectures

Red Hat Enterprise Linux HPC Node EUS (v. 6.6) - noarch, x86_64

Red Hat Enterprise Linux HPC Node Optional EUS (v. 6.6) - x86_64

Red Hat Enterprise Linux Server EUS (v. 6.6) - i386, noarch, ppc64, s390x, x86_64

Red Hat Enterprise Linux Server Optional EUS (v. 6.6) - i386, ppc64, s390x, x86_64

Bugs Fixed

1310570 - CVE-2016-4565 kernel: infiniband: Unprivileged process can overwrite kernel memory using rdma_ucm.ko

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