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.