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Red Hat Enterprise Linux 3: RHSA-2011:0840-01 Critical: DHCP Code Exec Risk

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Calendar Grey May 31, 2011
Scroller Redhat
The latest security patch from Red Hat tackles a critical vulnerability that could allow unwarranted code execution. Update your systems immediately for enhanced protection!
Updated dhcp packages that fix one security issue are now available for Red Hat Enterprise Linux 3 Extended Life Cycle Support

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.

Topics%20covered

Topics Covered

security advisory security issue code execution important red hat enterprise linux network configuration dhcp update

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 (v. 3 ELS):
Source: dhcp-3.0.1-10.3_EL3.src.rpm
i386: dhclient-3.0.1-10.3_EL3.i386.rpm dhcp-3.0.1-10.3_EL3.i386.rpm dhcp-debuginfo-3.0.1-10.3_EL3.i386.rpm dhcp-devel-3.0.1-10.3_EL3.i386.rpm
Red Hat Enterprise Linux ES (v. 3 ELS):
Source: dhcp-3.0.1-10.3_EL3.src.rpm
i386: dhclient-3.0.1-10.3_EL3.i386.rpm dhcp-3.0.1-10.3_EL3.i386.rpm dhcp-debuginfo-3.0.1-10.3_EL3.i386.rpm dhcp-devel-3.0.1-10.3_EL3.i386.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#package


Severity
important
Lowest
Low
Medium
High
Critical

Advisory ID: RHSA-2011:0840-01
Product: Red Hat Enterprise Linux
Advisory URL: https://access.redhat.com/errata/RHSA-2011:0840.html
Issue date: 2011-05-31

Topic

Updated dhcp packages that fix one security issue are now available forRed Hat Enterprise Linux 3 Extended Life Cycle Support.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.

Topics%20covered

Topics Covered

security advisory security issue code execution important red hat enterprise linux network configuration dhcp update

Relevant Releases Architectures

Red Hat Enterprise Linux AS (v. 3 ELS) - i386

Red Hat Enterprise Linux ES (v. 3 ELS) - i386

Bugs Fixed

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

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