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Alerts This Week
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Red Hat: RHSA-2011-0428-01 Important: dhcp Security Flaw Fixed

red hat
Calendar Grey April 8, 2011
Scroller Redhat
Ubuntu has published a critical OpenSSL vulnerability fix tackling a potential data breach risk. Immediate update advised.
Updated dhcp packages that fix one security issue are now available for Red Hat Enterprise Linux 4, 5, and 6

Solution

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

This update is available via the Red Hat Network. Details on how to use the Red Hat Network to apply this update are available at https://access.redhat.com/kb/docs/DOC-11259

Summary

The Dynamic Host Configuration Protocol (DHCP) is a protocol that allows individual devices on an IP network to get their own network configuration information, including an IP address, a subnet mask, and a broadcast address.
It was discovered that the DHCP client daemon, dhclient, did not sufficiently sanitize certain options provided in DHCP server replies, such as the client hostname. A malicious DHCP server could send such an option with a specially-crafted value to a DHCP client. If this option's value was saved on the client system, and then later insecurely evaluated by a process that assumes the option is trusted, it could lead to arbitrary code execution with the privileges of that process. (CVE-2011-0997)
Red Hat would like to thank Sebastian Krahmer of the SuSE Security Team for reporting this issue.
All dhclient users should upgrade to these updated packages, which contain a backported patch to correct this issue.

References

https://access.redhat.com/security/cve/CVE-2011-0997 https://access.redhat.com/security/updates/classification/#important

Package List

Red Hat Enterprise Linux AS version 4:
Source:
i386: dhclient-3.0.1-67.el4.i386.rpm dhcp-3.0.1-67.el4.i386.rpm dhcp-debuginfo-3.0.1-67.el4.i386.rpm dhcp-devel-3.0.1-67.el4.i386.rpm
ia64: dhclient-3.0.1-67.el4.ia64.rpm dhcp-3.0.1-67.el4.ia64.rpm dhcp-debuginfo-3.0.1-67.el4.ia64.rpm dhcp-devel-3.0.1-67.el4.ia64.rpm
ppc: dhclient-3.0.1-67.el4.ppc.rpm dhcp-3.0.1-67.el4.ppc.rpm dhcp-debuginfo-3.0.1-67.el4.ppc.rpm dhcp-devel-3.0.1-67.el4.ppc.rpm
s390: dhclient-3.0.1-67.el4.s390.rpm dhcp-3.0.1-67.el4.s390.rpm dhcp-debuginfo-3.0.1-67.el4.s390.rpm dhcp-devel-3.0.1-67.el4.s390.rpm
s390x: dhclient-3.0.1-67.el4.s390x.rpm dhcp-3.0.1-67.el4.s390x.rpm dhcp-debuginfo-3.0.1-67.el4.s390x.rpm dhcp-devel-3.0.1-67.el4.s390x.rpm
x86_64: dhclient-3.0.1-67.el4.x86_64.rpm dhcp-3.0.1-67.el4.x86_64.rpm dhcp-debuginfo-3.0.1-67.el4.x86_64.rpm dhcp-devel-3.0.1-67.el4.x86_64.rpm
Red Hat Enterprise Linux Desktop version 4:
Source:
i386: dhclient-3.0.1-67.el4.i386.rpm dhcp-3.0.1-67.el4.i386.rpm dhcp-debuginfo-3.0.1-67.el4.i386.rpm dhcp-devel-3.0.1-67.el4.i386.rpm
x86_64: dhclient-3.0.1-67.el4.x86_64.rpm dhcp-3.0.1-67.el4.x86_64.rpm dhcp-debuginfo-3.0.1-67.el4.x86_64.rpm dhcp-devel-3.0.1-67.el4.x86_64.rpm
Red Hat Enterprise Linux ES version 4:
Source:
i386: dhclient-3.0.1-67.el4.i386.rpm

Read the Full Advisory


Severity
important
Lowest
Low
Medium
High
Critical

Advisory ID: RHSA-2011:0428-01
Product: Red Hat Enterprise Linux
Issue date: 2011-04-08

Topic

Updated dhcp packages that fix one security issue are now available forRed Hat Enterprise Linux 4, 5, and 6.The Red Hat Security Response Team has rated this update as havingimportant security impact. A Common Vulnerability Scoring System (CVSS)base score, which gives a detailed severity rating, is available from theCVE link in the References section.

Relevant Releases Architectures

RHEL Desktop Workstation (v. 5 client) - i386, x86_64

Red Hat Enterprise Linux (v. 5 server) - i386, ia64, ppc, s390x, x86_64

Red Hat Enterprise Linux AS version 4 - i386, ia64, ppc, s390, s390x, x86_64

Red Hat Enterprise Linux Desktop (v. 5 client) - i386, x86_64

Red Hat Enterprise Linux Desktop (v. 6) - i386, x86_64

Red Hat Enterprise Linux Desktop Optional (v. 6) - i386, x86_64

Red Hat Enterprise Linux Desktop version 4 - i386, x86_64

Red Hat Enterprise Linux ES version 4 - i386, ia64, x86_64

Red Hat Enterprise Linux HPC Node (v. 6) - x86_64

Red Hat Enterprise Linux HPC Node Optional (v. 6) - x86_64

Red Hat Enterprise Linux Server (v. 6) - i386, ppc64, s390x, x86_64

Red Hat Enterprise Linux Server Optional (v. 6) - i386, ppc64, s390x, x86_64

Red Hat Enterprise Linux WS version 4 - i386, ia64, x86_64

Red Hat Enterprise Linux Workstation (v. 6) - i386, x86_64

Red Hat Enterprise Linux Workstation Optional (v. 6) - i386, x86_64

Bugs Fixed

689832 - CVE-2011-0997 dhclient: insufficient sanitization of certain DHCP response values

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