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Many people depend on Web Application Firewall to protect their applications without applying security on the application itself. They assume that it can make them secure automatically as it will thwart a lot of attacks. They also argue in favor of that. I don't say that WAFs are ineffective. I argue that your application should be secure itself in first place irrespective of WAF is deployed or not deployed. WAFs are also vulnerable and can be bypassed then its only your application security mechanism can thwart the attacks. Lots of time researchers have shown how to bypass WAFs.
But recently I came across a nice post by Sando Gauci of EnableSecurity in which he exploited the XSS in admin interface of a WAF and disabled the WAF completely. So the application behind can be reached without any restriction! I found it very useful to teach people and to stress on application security. Here is the attack in action.

Demo of a cross site scripting in dotDefender's admin interface from Sandro Gauci on Vimeo.


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