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

USN-3586-2: DHCP vulnerabilities

Publication date

28 May 2018

Overview

Several security issues were fixed in DHCP.

Releases

Packages

Details

USN-3586-1 fixed a vulnerability in DHCP. This update provides
the corresponding update for Ubuntu 12.04 ESM.

Original advisory details:

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)

USN-3586-1 fixed a vulnerability in DHCP. This update provides
the corresponding update for Ubuntu 12.04 ESM.

Original advisory details:

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
12.04 precise isc-dhcp-server –  4.1.ESV-R4-0ubuntu5.13
isc-dhcp-relay –  4.1.ESV-R4-0ubuntu5.13
isc-dhcp-client –  4.1.ESV-R4-0ubuntu5.13
isc-dhcp-server-ldap –  4.1.ESV-R4-0ubuntu5.13

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References

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