NoNox

NoNox is a powerful software that keeps an eye on log files for potential threats such as repeated "failed password" events. Once the program identifies such patterns, it can take various actions, including running commands to mitigate the behavior and notifying the user. NoNox is highly customizable, allowing users to set their own time limits, files to monitor, and commands to execute.

As someone who is concerned with cybersecurity, I use NoNox to monitor for password-scanning attacks and block attacking hosts in real-time. However, it's important to note that using NoNox does come with some risks. For example, since NoNox must run as a user with sufficient rights, it could introduce new vulnerabilities that some systems may find unacceptable.

Additionally, any real-time automated intrusion detection and response system like NoNox requires careful thought when it comes to configuring its settings. There is a risk of denial of service attacks if the software is not set up properly, which would allow outsiders to lock out legitimate users through carefully crafted forged messages.

To use NoNox, you will need Java 1.4 or later. The latest release of NoNox includes minor documentation corrections and repackages the software as a tar. There is also a new startup/shutdown script for /etc/init.d.