1. Ubuntu Security Notices
  2. USN-3586-1

USN-3586-1: DHCP vulnerabilities

Publication date

1 March 2018

Overview

Several security issues were fixed in DHCP.

Releases

Packages

Details

Konstantin Orekhov discovered that the DHCP server incorrectly handled a
large number of concurrent TCP sessions. A remote attacker could possibly
use this issue to cause a denial of service. This issue only affected
Ubuntu 14.04 LTS and Ubuntu 16.04 LTS. (CVE-2016-2774)

It was discovered that the DHCP server incorrectly handled socket
descriptors. A remote attacker could possibly use this issue to cause a
denial of service. (CVE-2017-3144)

Felix Wilhelm discovered that the DHCP client incorrectly handled certain
malformed responses. A remote attacker could use this issue to cause the
DHCP client to crash, resulting in a denial of service, or possibly execute
arbitrary code. In the default installation, attackers would be isolated by
the dhclient AppArmor profile. (CVE-2018-5732)

Felix Wilhelm discovered that...

Konstantin Orekhov discovered that the DHCP server incorrectly handled a
large number of concurrent TCP sessions. A remote attacker could possibly
use this issue to cause a denial of service. This issue only affected
Ubuntu 14.04 LTS and Ubuntu 16.04 LTS. (CVE-2016-2774)

It was discovered that the DHCP server incorrectly handled socket
descriptors. A remote attacker could possibly use this issue to cause a
denial of service. (CVE-2017-3144)

Felix Wilhelm discovered that the DHCP client incorrectly handled certain
malformed responses. A remote attacker could use this issue to cause the
DHCP client to crash, resulting in a denial of service, or possibly execute
arbitrary code. In the default installation, attackers would be isolated by
the dhclient AppArmor profile. (CVE-2018-5732)

Felix Wilhelm discovered that the DHCP server incorrectly handled reference
counting. A remote attacker could possibly use this issue to cause the DHCP
server to crash, resulting in a denial of service. (CVE-2018-5733)

Update instructions

In general, a standard system update will make all the necessary changes.

Learn more about how to get the fixes.

The problem can be corrected by updating your system to the following package versions:

Ubuntu Release Package Version
17.10 artful isc-dhcp-client –  4.3.5-3ubuntu2.2
isc-dhcp-relay –  4.3.5-3ubuntu2.2
isc-dhcp-server –  4.3.5-3ubuntu2.2
isc-dhcp-server-ldap –  4.3.5-3ubuntu2.2
16.04 xenial isc-dhcp-client –  4.3.3-5ubuntu12.9
isc-dhcp-relay –  4.3.3-5ubuntu12.9
isc-dhcp-server –  4.3.3-5ubuntu12.9
isc-dhcp-server-ldap –  4.3.3-5ubuntu12.9
14.04 trusty isc-dhcp-client –  4.2.4-7ubuntu12.12
isc-dhcp-relay –  4.2.4-7ubuntu12.12
isc-dhcp-server –  4.2.4-7ubuntu12.12
isc-dhcp-server-ldap –  4.2.4-7ubuntu12.12

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References

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