Moderate: dhcp security, bug fix, and enhancement update

Related Vulnerabilities: CVE-2016-2774   CVE-2016-2774   CVE-2016-2774  

Synopsis

Moderate: dhcp security, bug fix, and enhancement update

Type/Severity

Security Advisory: Moderate

Topic

An update for dhcp is now available for Red Hat Enterprise Linux 7.

Red Hat Product Security has rated this update as having a security impact of Moderate. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) 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. The dhcp packages provide a relay agent and ISC DHCP service required to enable and administer DHCP on a network.

Security Fix(es):

  • A resource-consumption flaw was discovered in the DHCP server. dhcpd did not restrict the number of open connections to OMAPI and failover ports. A remote attacker able to establish TCP connections to one of these ports could use this flaw to cause dhcpd to exit unexpectedly, stop responding requests, or exhaust system sockets (denial of service). (CVE-2016-2774)

Red Hat would like to thank ISC for reporting this issue.

Additional Changes:

For detailed information on changes in this release, see the Red Hat Enterprise Linux 7.3 Release Notes linked from the References section.

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

Affected Products

  • Red Hat Enterprise Linux Server 7 x86_64
  • Red Hat Enterprise Linux Server - Extended Update Support 7.6 x86_64
  • Red Hat Enterprise Linux Server - Extended Update Support 7.5 x86_64
  • Red Hat Enterprise Linux Server - Extended Update Support 7.4 x86_64
  • Red Hat Enterprise Linux Server - Extended Update Support 7.3 x86_64
  • Red Hat Enterprise Linux Server - AUS 7.6 x86_64
  • Red Hat Enterprise Linux Server - AUS 7.4 x86_64
  • Red Hat Enterprise Linux Workstation 7 x86_64
  • Red Hat Enterprise Linux Desktop 7 x86_64
  • Red Hat Enterprise Linux for IBM z Systems 7 s390x
  • Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 7.6 s390x
  • Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 7.5 s390x
  • Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 7.4 s390x
  • Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 7.3 s390x
  • Red Hat Enterprise Linux for Power, big endian 7 ppc64
  • Red Hat Enterprise Linux for Power, big endian - Extended Update Support 7.6 ppc64
  • Red Hat Enterprise Linux for Power, big endian - Extended Update Support 7.5 ppc64
  • Red Hat Enterprise Linux for Power, big endian - Extended Update Support 7.4 ppc64
  • Red Hat Enterprise Linux for Power, big endian - Extended Update Support 7.3 ppc64
  • Red Hat Enterprise Linux for Scientific Computing 7 x86_64
  • Red Hat Enterprise Linux EUS Compute Node 7.6 x86_64
  • Red Hat Enterprise Linux EUS Compute Node 7.5 x86_64
  • Red Hat Enterprise Linux EUS Compute Node 7.4 x86_64
  • Red Hat Enterprise Linux EUS Compute Node 7.3 x86_64
  • Red Hat Enterprise Linux Server - AUS 7.3 x86_64
  • Red Hat Enterprise Linux for Power, little endian 7 ppc64le
  • Red Hat Enterprise Linux for Power, little endian - Extended Update Support 7.6 ppc64le
  • Red Hat Enterprise Linux for Power, little endian - Extended Update Support 7.5 ppc64le
  • Red Hat Enterprise Linux for Power, little endian - Extended Update Support 7.4 ppc64le
  • Red Hat Enterprise Linux for Power, little endian - Extended Update Support 7.3 ppc64le
  • Red Hat Enterprise Linux Server - TUS 7.6 x86_64
  • Red Hat Enterprise Linux Server - TUS 7.3 x86_64
  • Red Hat Enterprise Linux Server (for IBM Power LE) - Update Services for SAP Solutions 7.6 ppc64le
  • Red Hat Enterprise Linux Server (for IBM Power LE) - Update Services for SAP Solutions 7.4 ppc64le
  • Red Hat Enterprise Linux Server (for IBM Power LE) - Update Services for SAP Solutions 7.3 ppc64le
  • Red Hat Enterprise Linux Server - Update Services for SAP Solutions 7.6 x86_64
  • Red Hat Enterprise Linux Server - Update Services for SAP Solutions 7.4 x86_64
  • Red Hat Enterprise Linux Server - Update Services for SAP Solutions 7.3 x86_64

Fixes

  • BZ - 1315259 - CVE-2016-2774 dhcp: unclosed TCP connections to OMAPI or failover ports can cause DoS

CVEs

References