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Red Hat 6.5/6.6 RHSA-2015-2520 Important NTP Synchronization Issue

red hat
Calendar Grey November 26, 2015
Scroller Redhat
Crucial safety patch released for ntp in Red Hat Enterprise Linux versions 6.5 and 6.6 correcting a significant vulnerability.
Updated ntp packages that fix one security issue are now available for Red Hat Enterprise Linux 6.5 and 6.6 Extended Update Support

Solution

Before applying this update, make sure all previously released errata relevant to your system have been applied.

For details on how to apply this update, refer to:

https://access.redhat.com/articles/11258

Summary

The Network Time Protocol (NTP) is used to synchronize a computer's time with a referenced time source.
It was discovered that ntpd as a client did not correctly check timestamps in Kiss-of-Death packets. A remote attacker could use this flaw to send a crafted Kiss-of-Death packet to an ntpd client that would increase the client's polling interval value, and effectively disable synchronization with the server. (CVE-2015-7704)
Red Hat would like to thank Aanchal Malhotra, Isaac E. Cohen, and Sharon Goldberg of Boston University for reporting this issue.
All ntp users are advised to upgrade to these updated packages, which contain a backported patch to resolve this issue. After installing the update, the ntpd daemon will restart automatically.

Topics%20covered

Topics Covered

security advisory security issue Red Hat important synchronization ntp

References

https://access.redhat.com/security/cve/CVE-2015-7704 https://access.redhat.com/security/updates/classification/#important

Package List

Red Hat Enterprise Linux HPC Node EUS (v. 6.5):
Source: ntp-4.2.6p5-2.el6_5.1.src.rpm
x86_64: ntp-4.2.6p5-2.el6_5.1.x86_64.rpm ntp-debuginfo-4.2.6p5-2.el6_5.1.x86_64.rpm ntpdate-4.2.6p5-2.el6_5.1.x86_64.rpm
Red Hat Enterprise Linux HPC Node EUS (v. 6.6):
Source: ntp-4.2.6p5-3.el6_6.1.src.rpm
x86_64: ntp-4.2.6p5-3.el6_6.1.x86_64.rpm ntp-debuginfo-4.2.6p5-3.el6_6.1.x86_64.rpm ntpdate-4.2.6p5-3.el6_6.1.x86_64.rpm
Red Hat Enterprise Linux Compute Node Optional EUS (v. 6.5):
Source: ntp-4.2.6p5-2.el6_5.1.src.rpm
noarch: ntp-doc-4.2.6p5-2.el6_5.1.noarch.rpm
x86_64: ntp-debuginfo-4.2.6p5-2.el6_5.1.x86_64.rpm ntp-perl-4.2.6p5-2.el6_5.1.x86_64.rpm
Red Hat Enterprise Linux Compute Node Optional EUS (v. 6.6):
noarch: ntp-doc-4.2.6p5-3.el6_6.1.noarch.rpm
x86_64: ntp-debuginfo-4.2.6p5-3.el6_6.1.x86_64.rpm ntp-perl-4.2.6p5-3.el6_6.1.x86_64.rpm
Red Hat Enterprise Linux Server EUS (v. 6.5):
Source: ntp-4.2.6p5-2.el6_5.1.src.rpm
i386: ntp-4.2.6p5-2.el6_5.1.i686.rpm ntp-debuginfo-4.2.6p5-2.el6_5.1.i686.rpm ntpdate-4.2.6p5-2.el6_5.1.i686.rpm
ppc64: ntp-4.2.6p5-2.el6_5.1.ppc64.rpm ntp-debuginfo-4.2.6p5-2.el6_5.1.ppc64.rpm ntpdate-4.2.6p5-2.el6_5.1.ppc64.rpm
s390x: ntp-4.2.6p5-2.el6_5.1.s390x.rpm ntp-debuginfo-4.2.6p5-2.el6_5.1.s390x.rpm ntpdate-4.2.6p5-2.el6_5.1.s390x.rpm
x86_64:

Read the Full Advisory


Severity
important
Lowest
Low
Medium
High
Critical

Advisory ID: RHSA-2015:2520-01
Product: Red Hat Enterprise Linux
Advisory URL: https://access.redhat.com/errata/RHSA-2015:2520.html
Issue date: 2015-11-26

Topic

Updated ntp packages that fix one security issue are now available for RedHat Enterprise Linux 6.5 and 6.6 Extended Update Support.Red Hat Product Security has rated this update as having Important securityimpact. A Common Vulnerability Scoring System (CVSS) base score, whichgives a detailed severity rating, is available from the CVE link in theReferences section.

Topics%20covered

Topics Covered

security advisory security issue Red Hat important synchronization ntp

Relevant Releases Architectures

Red Hat Enterprise Linux Compute Node Optional EUS (v. 6.5) - noarch, x86_64

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

Red Hat Enterprise Linux HPC Node EUS (v. 6.5) - x86_64

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

Red Hat Enterprise Linux Server EUS (v. 6.5) - i386, ppc64, s390x, x86_64

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

Red Hat Enterprise Linux Server Optional EUS (v. 6.5) - i386, noarch, ppc64, s390x, x86_64

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

Bugs Fixed

1271070 - CVE-2015-7704 ntp: disabling synchronization via crafted KoD packet

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