USN-3586-1: DHCP vulnerabilities
isc-dhcp vulnerabilities
A security issue affects these releases of Ubuntu and its derivatives:
- Ubuntu 17.10
- Ubuntu 16.04 LTS
- Ubuntu 14.04 LTS
Summary
Several security issues were fixed in DHCP.
Software Description
- isc-dhcp - DHCP server and client
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 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
The problem can be corrected by updating your system to the following package versions:
- Ubuntu 17.10
- 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
- Ubuntu 16.04 LTS
- 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
- Ubuntu 14.04 LTS
- 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
To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.
In general, a standard system update will make all the necessary changes.
References
from Ubuntu Security Notices http://ift.tt/2Fj7VWM