RHEL 6 / 7 : ISC DHCP Concurrent TCP Sessions DoS

high Nessus Plugin ID 90250

Synopsis

The remote host is affected by a denial of service vulnerability.

Description

RedHat Enterprise Linux 6 / 7 is affected by a denial of service vulnerability in the bundled ISC DHCP server due to a failure to properly restrict the number of concurrent TCP sessions to the ports the server uses for inter-process communications and control. An unauthenticated, remote attacker can exploit this, by opening a large number of TCP sessions, to cause the server to fail to process requests or to exit unexpectedly, or to cause an exhaustion of system sockets.

Note that this vulnerability is more easily exploited when the DHCP server is using OMAPI for remote management.

Solution

Restrict access to the DHCP server to trusted networks and peers only.

Note that RedHat, at this time, has deferred the fix for RedHat Enterprise Linux 6 / 7 to a later date.

See Also

https://access.redhat.com/security/cve/cve-2016-2774

https://kb.isc.org/article/AA-01354

Plugin Details

Severity: High

ID: 90250

File Name: redhat-isc-dhcp-CVE-2016-2774.nasl

Version: 1.5

Type: local

Agent: unix

Published: 3/29/2016

Updated: 7/27/2018

Supported Sensors: Agentless Assessment, Frictionless Assessment Agent, Frictionless Assessment AWS, Frictionless Assessment Azure, Nessus Agent

Risk Information

VPR

Risk Factor: Low

Score: 3.6

CVSS v2

Risk Factor: High

Base Score: 7.8

Temporal Score: 5.8

Vector: AV:N/AC:L/Au:N/C:N/I:N/A:C

Temporal Vector: E:U/RL:OF/RC:C

Vulnerability Information

CPE: cpe:/o:redhat:enterprise_linux

Required KB Items: Host/local_checks_enabled, Host/RedHat/release, Host/RedHat/rpm-list, Host/cpu

Exploit Ease: No known exploits are available

Vulnerability Publication Date: 3/7/2016

Reference Information

CVE: CVE-2016-2774