Preventing spam injection

[kkbbzzaa]

Hi, I want to prevent spam injection in my forms. If the user inputs something like: sender@example.com%OABcc:victim@somesite.com, the server outputs a 404 error.

Not Acceptable
An appropriate representation of the requested resource /feng/en/trial.php could not be found on this server.

Additionally, a 404 Not Found error was encountered while trying to use an ErrorDocument to handle the request.

This gives me no opportunity to fix the injection with php using htmlspecialchars() and urldecode().

Any ideas how to fix this??

Regards

Mateo

[AndrewT]

There server specifically looks for the bcc: condition in form submissions as this is very commonly injected to send spam. As such, these requests are blocked.

[ZYV]

It's a 406 Error, not 404, which means that mod_security already intercepted and blocked the request.