Moderate: dhcp security update

Related Vulnerabilities: CVE-2011-4539   CVE-2011-4539   cve-2011-4539  

Synopsis

Moderate: dhcp security update

Type/Severity

Security Advisory: Moderate

Topic

Updated dhcp packages that fix one security issue are now available for
Red Hat Enterprise Linux 6.

The Red Hat Security Response Team has rated this update as having moderate
security impact. A Common Vulnerability Scoring System (CVSS) base score,
which gives a detailed severity rating, is available from the CVE link in
the References section.

Description

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.

A denial of service flaw was found in the way the dhcpd daemon handled DHCP
request packets when regular expression matching was used in
"/etc/dhcp/dhcpd.conf". A remote attacker could use this flaw to crash
dhcpd. (CVE-2011-4539)

Users of DHCP should upgrade to these updated packages, which contain a
backported patch to correct this issue. After installing this update, all
DHCP servers will be restarted automatically.

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

Affected Products

  • Red Hat Enterprise Linux Server 6 x86_64
  • Red Hat Enterprise Linux Server 6 i386
  • Red Hat Enterprise Linux Server - Extended Update Support 6.2 x86_64
  • Red Hat Enterprise Linux Server - Extended Update Support 6.2 i386
  • Red Hat Enterprise Linux Workstation 6 x86_64
  • Red Hat Enterprise Linux Workstation 6 i386
  • Red Hat Enterprise Linux Desktop 6 x86_64
  • Red Hat Enterprise Linux Desktop 6 i386
  • Red Hat Enterprise Linux for IBM z Systems 6 s390x
  • Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 6.2 s390x
  • Red Hat Enterprise Linux for Power, big endian 6 ppc64
  • Red Hat Enterprise Linux for Power, big endian - Extended Update Support 6.2 ppc64
  • Red Hat Enterprise Linux for Scientific Computing 6 x86_64
  • Red Hat Enterprise Linux Server from RHUI 6 x86_64
  • Red Hat Enterprise Linux Server from RHUI 6 i386
  • Red Hat Enterprise Linux Server - Extended Update Support from RHUI 6.2 x86_64
  • Red Hat Enterprise Linux Server - Extended Update Support from RHUI 6.2 i386
  • Red Hat Storage 2.0 x86_64
  • Red Hat Gluster Storage Server for On-premise 2.0 x86_64
  • Red Hat Storage for Public Cloud (via RHUI) 2.0 x86_64
  • Red Hat Enterprise Linux Server - AUS 6.2 x86_64

Fixes

  • BZ - 761265 - CVE-2011-4539 dhcp: DoS due to processing certain regular expressions

CVEs

References