Squidefender is a Perl script which analyzes a squid log file in native format to detect attacks. If it finds an attack, it sends a complaint email to the ISP of the attacker. It also has the option to execute an external command to take other actions. This can be used to automatically adapt your firewall when an attack has occured. The power of squidefender lies in its configuration options, which let you easily add new attacks to scan for. Another interesting option of squidefender is its ability to use different message templates based on the attack found.
WormWarner is a Perl script that is used to warn hosts that are probably infected by a worm. It decides wether a host is infected by analyzing the data from the Apache log files. It currently recognizes CodeRed, Nimda, the Linux.Slapper.Worm, and the FreeBSD.Scalper.worm. Warning is done by trying to contact the SMTP server on the infected host and sending an email to the postmaster.