Rule Category

OS-LINUX -- Snort has detected traffic targeting vulnerabilities in a Linux-based operating system. This does not include browser traffic or other software on the OS, but attacks against the OS itself. (such as?)

Alert Message

OS-LINUX Red Hat NetworkManager DHCP client command injection attempt

Rule Explanation

This event is generated when an attempt to exploit a vulnerability in Red Hat's NetworkManager DHCP client is detected Impact: Attempted User Privilege Gain Details: The DHCP protocol is used to configure network related information in hosts from a central server. When a host is connected to a network, it can issue DHCP requests to fetch network configuration parameter such as IP address, default router IP, DNS servers, and more. The DHCP client package dhclient provided by Red Hat has a script /etc/NetworkManager/dispatcher.d/11-dhclient (in Red Hat Enterprise Linux 7) or /etc/NetworkManager/dispatcher.d/10-dhclient (in Red Hat Enterprise Linux 6) for the NetworkManager component, which is executed each time NetworkManager receives a DHCP response from a DHCP server. A malicious DHCP response could cause the script to execute arbitrary shell commands with root privileges. Ease of Attack: Medium

What To Look For

Known Usage

No public information

False Positives

No known false positives

Contributors

Cisco Talos Intelligence Group

MITRE ATT&CK Framework

Tactic:

Technique:

For reference, see the MITRE ATT&CK vulnerability types here: https://attack.mitre.org

CVE

Additional Links

CVE Additional Information

CVE-2018-1111
DHCP packages in Red Hat Enterprise Linux 6 and 7, Fedora 28, and earlier are vulnerable to a command injection flaw in the NetworkManager integration script included in the DHCP client. A malicious DHCP server, or an attacker on the local network able to spoof DHCP responses, could use this flaw to execute arbitrary commands with root privileges on systems using NetworkManager and configured to obtain network configuration using the DHCP protocol.
Details
Severity Base Score7.5
Impact Score5.9 Exploit Score1.6
Confidentiality ImpactHIGH Integrity ImpactHIGH
Availability ImpactHIGH Access Vector
Authentication Ease of Access