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Red Hat Enterprise Linux 7: RHSA-2016:2590-02 Moderate: DHCP DoS

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Calendar Grey November 3, 2016
Scroller Redhat
Cautionary security alert for Red Hat regarding DHCP vulnerabilities and updates pertaining to system improvements.
An update for dhcp is now available for Red Hat Enterprise Linux 7

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

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. 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.

Topics%20covered

Topics Covered

security advisory security update DoS Red Hat Enterprise Linux dhcp Moderate

References

https://access.redhat.com/security/cve/CVE-2016-2774 https://access.redhat.com/security/updates/classification#moderate https://docs.redhat.com/en/documentation/Red_Hat_Enterprise_Linux/7/html/7.3_Release_Notes/index.html

Package List

Red Hat Enterprise Linux Client (v. 7):
Source: dhcp-4.2.5-47.el7.src.rpm
x86_64: dhclient-4.2.5-47.el7.x86_64.rpm dhcp-common-4.2.5-47.el7.x86_64.rpm dhcp-debuginfo-4.2.5-47.el7.i686.rpm dhcp-debuginfo-4.2.5-47.el7.x86_64.rpm dhcp-libs-4.2.5-47.el7.i686.rpm dhcp-libs-4.2.5-47.el7.x86_64.rpm
Red Hat Enterprise Linux Client Optional (v. 7):
x86_64: dhcp-4.2.5-47.el7.x86_64.rpm dhcp-debuginfo-4.2.5-47.el7.i686.rpm dhcp-debuginfo-4.2.5-47.el7.x86_64.rpm dhcp-devel-4.2.5-47.el7.i686.rpm dhcp-devel-4.2.5-47.el7.x86_64.rpm
Red Hat Enterprise Linux ComputeNode (v. 7):
Source: dhcp-4.2.5-47.el7.src.rpm
x86_64: dhclient-4.2.5-47.el7.x86_64.rpm dhcp-common-4.2.5-47.el7.x86_64.rpm dhcp-debuginfo-4.2.5-47.el7.i686.rpm dhcp-debuginfo-4.2.5-47.el7.x86_64.rpm dhcp-libs-4.2.5-47.el7.i686.rpm dhcp-libs-4.2.5-47.el7.x86_64.rpm
Red Hat Enterprise Linux ComputeNode Optional (v. 7):
x86_64: dhcp-4.2.5-47.el7.x86_64.rpm dhcp-debuginfo-4.2.5-47.el7.i686.rpm dhcp-debuginfo-4.2.5-47.el7.x86_64.rpm dhcp-devel-4.2.5-47.el7.i686.rpm dhcp-devel-4.2.5-47.el7.x86_64.rpm
Red Hat Enterprise Linux Server (v. 7):
Source: dhcp-4.2.5-47.el7.src.rpm
aarch64: dhclient-4.2.5-47.el7.aarch64.rpm dhcp-4.2.5-47.el7.aarch64.rpm dhcp-common-4.2.5-47.el7.aarch64.rpm dhcp-debuginfo-4.2.5-47.el7.aarch64.rpm

Read the Full Advisory


Advisory ID: RHSA-2016:2590-02
Product: Red Hat Enterprise Linux
Advisory URL: https://access.redhat.com/errata/RHSA-2016:2590.html
Issue date: 2016-11-03

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 impactof Moderate. A Common Vulnerability Scoring System (CVSS) base score, whichgives a detailed severity rating, is available for each vulnerability fromthe CVE link(s) in the References section.

Topics%20covered

Topics Covered

security advisory security update DoS Red Hat Enterprise Linux dhcp Moderate

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

Bugs Fixed

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

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