InjectionAttackFilter is a subclass of HttpServletRequestWrapper that will protect against common sql injection and cross-site scripting attacks. 

The filter will look at inbound request parameters, and remove any suspicious characters, letting the remaining data through. If someone submits a parameter:

name="<script>alert('hi!');</script>"

your application will see the harmless:

name="scriptalert('hi!');script"

I chose to do this because I generally want to have incomplete data rather than no data. Also, there could be some situation where an end user has a name that triggers the filter. In that case, I'd rather have partial legitimate user data rather than none. Future enhancements will allow you to totally block any parameter that is suspicious.


It's covered under the MIT license.

Copyright (c) 2011 Andrew C Slocum

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.