Detect potential HPP attack vectors.
HTTP Parameter Pollution (HPP) is a recently discovered web exploitation technique. Please read the NDSS 2010 paper for more details about the technique. HPP Finder is a Chrome extension designed for detecting HPP attempts. HPP Finder can detect URLs and HTML forms that might be susceptible of parameter pollution, but it is not a complete solution against HPP.
See example at: http://www.ics.forth.gr/~elathan/extra/hpp/index.html