Overly broad permissions can turn one compromised account into a much larger security problem. Learn how to reduce unnecessary access, review privileges, and apply least privilege across modern Linux systems. Review Linux Privileges×

Alerts This Week
Warning Icon 1 524
Alerts This Week
Warning Icon 1 524

Red Hat Enterprise MRG 6 Critical: RHSA-2016:1631-01 Networking Bug

red hat
Calendar Grey August 18, 2016
Scroller Redhat
Ubuntu rolls out significant patch for kernel-lts, addressing vital connectivity vulnerabilities and enhancing system stability.
An update for kernel-rt is now available for Red Hat Enterprise MRG 2.5

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.
It was found that the RFC 5961 challenge ACK rate limiting as implemented in the Linux kernel's networking subsystem allowed an off-path attacker to leak certain information about a given connection by creating congestion on the global challenge ACK rate limit counter and then measuring the changes by probing packets. An off-path attacker could use this flaw to either terminate TCP connection and/or inject payload into non-secured TCP connection between two endpoints on the network. (CVE-2016-5696, Important)
Red Hat would like to thank Yue Cao from Cyber Security Group in the CS department of University of California, Riverside, for reporting this issue.

Topics%20covered

Topics Covered

security advisory important information disclosure networking issue kernel-rt Red Hat Enterprise MRG real-time kernel

References

https://access.redhat.com/security/cve/CVE-2016-5696 https://access.redhat.com/security/updates/classification/#important

Package List

MRG Realtime for RHEL 6 Server v.2:
Source: kernel-rt-3.10.0-327.rt56.195.el6rt.src.rpm
noarch: kernel-rt-doc-3.10.0-327.rt56.195.el6rt.noarch.rpm kernel-rt-firmware-3.10.0-327.rt56.195.el6rt.noarch.rpm
x86_64: kernel-rt-3.10.0-327.rt56.195.el6rt.x86_64.rpm kernel-rt-debug-3.10.0-327.rt56.195.el6rt.x86_64.rpm kernel-rt-debug-debuginfo-3.10.0-327.rt56.195.el6rt.x86_64.rpm kernel-rt-debug-devel-3.10.0-327.rt56.195.el6rt.x86_64.rpm kernel-rt-debuginfo-3.10.0-327.rt56.195.el6rt.x86_64.rpm kernel-rt-debuginfo-common-x86_64-3.10.0-327.rt56.195.el6rt.x86_64.rpm kernel-rt-devel-3.10.0-327.rt56.195.el6rt.x86_64.rpm kernel-rt-trace-3.10.0-327.rt56.195.el6rt.x86_64.rpm kernel-rt-trace-debuginfo-3.10.0-327.rt56.195.el6rt.x86_64.rpm kernel-rt-trace-devel-3.10.0-327.rt56.195.el6rt.x86_64.rpm kernel-rt-vanilla-3.10.0-327.rt56.195.el6rt.x86_64.rpm kernel-rt-vanilla-debuginfo-3.10.0-327.rt56.195.el6rt.x86_64.rpm kernel-rt-vanilla-devel-3.10.0-327.rt56.195.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-2016:1631-01
Product: Red Hat Enterprise MRG for RHEL-6
Advisory URL: https://access.redhat.com/errata/RHSA-2016:1631.html
Issue date: 2016-08-18

Topic

An update for kernel-rt is now available for Red Hat Enterprise MRG 2.5.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 important information disclosure networking issue kernel-rt Red Hat Enterprise MRG real-time kernel

Relevant Releases Architectures

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

Bugs Fixed

1354708 - CVE-2016-5696 kernel: challenge ACK counter information disclosure.

Get the latest News and Insights

Get the latest Linux and open source security news straight to your inbox.