7.1 - RHSA-2016:2590

Problem Description:

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.

2. Relevant releases/architectures:

Red Hat Enterprise Linux Client (v. 7) - x86_64 Red Hat Enterprise Linux Client Optional (v. 7) - x86_64 Red Hat Enterprise Linux ComputeNode (v. 7) - x86_64 Red Hat Enterprise Linux ComputeNode Optional (v. 7) - x86_64 Red Hat Enterprise Linux Server (v. 7) - aarch64, ppc64, ppc64le, s390x, x86_64 Red Hat Enterprise Linux Server Optional (v. 7) - aarch64, ppc64, ppc64le, s390x, x86_64 Red Hat Enterprise Linux Workstation (v. 7) - x86_64 Red Hat Enterprise Linux Workstation Optional (v. 7) - x86_64

3. 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.

4. 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

5. Bugs fixed (https://bugzilla.redhat.com/):

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