CVE-2016-2774

ISC DHCP 4.1.x before 4.1-ESV-R13 and 4.2.x and 4.3.x before 4.3.4 does not restrict the number of concurrent TCP sessions, which allows remote attackers to cause a denial of service (INSIST assertion failure or request-processing outage) by establishing many sessions.

This update for dhcp fixes the following issues:

• CVE-2016-2774: Fixed a denial of service attack against the DHCP server over the OMAPI TCP socket, which could be used by network adjacent attackers to make the DHCP server non-functional (bsc#969820).

This update for dhcp fixes the following issues:

• CVE-2016-2774: Fixed a denial of service attack against the DHCP server over the OMAPI TCP socket, which could be used by network adjacent attackers to make the DHCP server non-functional (bsc#969820).

This update for dhcp fixes the following issues:

Security issue fixed:

• CVE-2016-2774: Fixed a denial of service attack against the DHCP server over the OMAPI TCP socket, which could be used by network adjacent attackers to make the DHCP server non-functional (bsc#969820).

Non security issues fixed:

• Rename freeaddrinfo(), getaddrinfo() and getnameinfo() in the internal libirs library that does not consider /etc/hosts and /etc/nsswitch.conf to use irs_ prefix. This prevents name conflicts which would result in overriding standard glibc functions used by libldap. (bsc#972907)

This update for dhcp fixes the following issues:

• CVE-2016-2774: Fixed a denial of service attack against the DHCP server over the OMAPI TCP socket, which could be used by network adjacent attackers to make the DHCP server non-functional (bsc#969820).

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)