US Patent 9438625 Mitigating scripted attacks using dynamic polymorphism

In an embodiment, a data processing system comprises one or more processors; script analysis logic coupled to the one or more processors and configured to obtain a particular electronic document from a server computer; script injection logic coupled to the one or more processors and configured to insert a set of script code into source code of the electronic document to result in producing a modified electronic document prior to providing the modified electronic document to a client computer; wherein the script code is configured to improve resistance of the client computer to attacks by running upon loading in the client computer and to cause transforming, when running in the client computer, one or more values of one or more elements of the source code of the electronic document into obfuscated values of the one or more elements. As a result, the system and method herein improve resistance of the client computer to attacks.