Ubuntu 15.10: 2868-1 Critical Denial Of Service in isc-dhcp

ubuntu

January 13, 2016

DHCP server, client, or relay could be made to crash if they received specially crafted network traffic.

Summary

DHCP server, client, or relay could be made to crash if they received

specially crafted network traffic.

Software Description:

- isc-dhcp: DHCP server and client

Details:

Sebastian Poehn discovered that the DHCP server, client, and relay

incorrectly handled certain malformed UDP packets. A remote attacker could

use this issue to cause the DHCP server, client, or relay to stop

responding, resulting in a denial of service.

Topics Covered

security advisory denial of service critical attack update instructions ubuntu isc-dhcp

Update Instructions

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

Ubuntu 15.10:
  isc-dhcp-client                 4.3.1-5ubuntu3.1
  isc-dhcp-relay                  4.3.1-5ubuntu3.1
  isc-dhcp-server                 4.3.1-5ubuntu3.1
  isc-dhcp-server-ldap            4.3.1-5ubuntu3.1

Ubuntu 15.04:
  isc-dhcp-client                 4.3.1-5ubuntu2.3
  isc-dhcp-relay                  4.3.1-5ubuntu2.3
  isc-dhcp-server                 4.3.1-5ubuntu2.3
  isc-dhcp-server-ldap            4.3.1-5ubuntu2.3

Ubuntu 14.04 LTS:
  isc-dhcp-client                 4.2.4-7ubuntu12.4
  isc-dhcp-relay                  4.2.4-7ubuntu12.4
  isc-dhcp-server                 4.2.4-7ubuntu12.4
  isc-dhcp-server-ldap            4.2.4-7ubuntu12.4

Ubuntu 12.04 LTS:
  isc-dhcp-client                 4.1.ESV-R4-0ubuntu5.10
  isc-dhcp-relay                  4.1.ESV-R4-0ubuntu5.10
  isc-dhcp-server                 4.1.ESV-R4-0ubuntu5.10
  isc-dhcp-server-ldap            4.1.ESV-R4-0ubuntu5.10

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