Detect attacks on your network with Maltrail - Sentry

Maltrail is a lightweight analysis tool that examines network traffic and raises the alarm if it detects suspicious access or dubious name resolution.

- Markus Stubbig

Hundreds of security products vie for the favor of users on the Internet, promising the highest levels of protection. Along with the numerous commercial offerings available for a monthly rate are some free open-source products that aim to expand the basic protection that might already be in place.

Maltrail [1] is an open source tool that lays in wait on the network and sounds the alarm if a package appears suspicious. It reports its findings but does not intervene. The way Maltrail works is somewhere between an intrusion detection system and a malware scanner. Maltrail uses public blacklists to examine the packages. In Maltrail jargon, the description of a suspicious IP address, web URL, or domain is known as a trail. Feeds are lists of known trails that the Maltrail community keeps up to date.

Structure

Maltrail consists of two components. The sensor component sniffs the packets, and the server component collects the alarms from the sensor. In a perfect setup, the sensor component resides on a router or firewall, because these devices get to see the data streams of all network participants. In Figure 1, the sensor resides on a firewall and therefore has access to all the packets passing through. The position of the server does not matter much as long as the sensor and the admin can access it.

Installation

The Maltrail program code is written entirely in Python. Maltrail is not picky about the Python version. Basically, all interpreters with a version number of 2.6 or newer will work, and this means that even older Linux servers can be used as sensors. The sensor also needs the Python pcapy package to intercept the IP packets from the network adapter. The software itself is available from Github under a free license.