Abstract: Techniques are provided for request modification for web security challenge. Data corresponding to a web page request by a client computing device for a web page is received. The web page comprises web code that allows a user to submit a request to initiate a web transaction with a web server system. Challenge code is generated that determines one or more values that are a valid solution to a challenge. The challenge code is provided for integrated code to be served in response to the web page request. The integrated code comprises the challenge code and modified web code that adds one or more parameters for the valid solution to the request. A particular request is received to initiate the web transaction. It is determined that the one or more parameter values are not a valid solution. In response, the web server system is prevented from processing the particular request.

Abstract: Techniques are provided for request modification for web security challenge. Data corresponding to a web page request by a client computing device for a web page is received. The web page comprises web code that allows a user to submit a request to initiate a web transaction with a web server system. Challenge code is generated that determines one or more values that are a valid solution to a challenge. The challenge code is provided for integrated code to be served in response to the web page request. The integrated code comprises the challenge code and modified web code that adds one or more parameters for the valid solution to the request. A particular request is received to initiate the web transaction. It is determined that the one or more parameter values are not a valid solution. In response, the web server system is prevented from processing the particular request.

Abstract: This document describes, among other things, a computer-implemented method for improving the security of one or more computing systems. The method can include receiving, at a computing system, first code that defines at least a portion of an electronic resource that is to be served to a client computing device. The method can include generating code that defines a challenge to be solved by the client computing device, in which the code is arranged to cause the client computing device to determine values for one or more parameters that comprise a solution to the challenge, and the values for the one or more parameters that comprise the solution to the challenge may be required for the client computing device to make valid requests to initiate one or more web-based transactions. The computing system can determine whether particular values for the parameters comprise a valid solution to the challenge.

Abstract: Techniques are provided for using instrumentation code to detect bots or malware. Data corresponding to requests from a plurality of client devices for a web resource comprising web code is obtained. The web resource is hosted by a first web server system. For a first client device of the plurality of client devices, instrumentation code is served. The instrumentation code is configured to execute on the first client device to monitor execution of the web code of the web resource at the first client device. One or more responses generated by the instrumentation code at the first client device are received from the first client device. The one or more responses are based one or more interactions with the web code at the first client device.

Abstract: A computer-implemented method for coordinating content transformation includes receiving, at a computer server subsystem and from a web server system, computer code to be served in response to a request from a computing client over the internet; modifying the computer code to obscure operation of the web server system that could be determined from the computer code; generating transformation information that is needed in order to reverse the modifications of the computer code to obscure the operation of the web server system; and serving to the computing client the modified code and the reverse transformation information.

Abstract: A computer-implemented method for coordinating content transformation includes receiving, at a computer server subsystem and from a web server system, computer code to be served in response to a request from a computing client over the internet; modifying the computer code to obscure operation of the web server system that could be determined from the computer code; generating transformation information that is needed in order to reverse the modifications of the computer code to obscure the operation of the web server system; and serving to the computing client the modified code and the reverse transformation information.

Abstract: Techniques are provided for using instrumentation code to detect bots or malware. Data corresponding to requests from a plurality of client devices for a web resource comprising web code is obtained. The web resource is hosted by a first web server system. For a first client device of the plurality of client devices, instrumentation code is served. The instrumentation code is configured to execute on the first client device to monitor execution of the web code of the web resource at the first client device. One or more responses generated by the instrumentation code at the first client device are received from the first client device. The one or more responses are based one or more interactions with the web code at the first client device.

Abstract: Techniques detecting the execution of alien content on a client computing device are provided. A set of web code is supplemented with a set of instrumentation code, which when executed at a client computing device, collects and reports information that describes execution of the set of web code at the client computing device, wherein the client computing device receives the set of web code and the set of instrumentation code. A set of information is received from the client computing device that is generated by the set of instrumentation code when the set of instrumentation code is executed at the client computing device. The presence of alien content interacting with the set of web code on the client computing device is determined based on the set of information.

Abstract: A computer-implemented method for identifying abnormal computer behavior includes receiving, at a computer server subsystem, data that characterizes subsets of particular document object models for web pages rendered by particular client computers; identifying clusters from the data that characterize the subsets of the particular document object models; and using the clusters to identify alien content on the particular client computers, wherein the alien content comprises content in the document object models that is not the result of content that is the basis of the document object model served.

Abstract: Techniques are provided for using instrumentation code to detect bots or malware. Data corresponding to requests from a plurality of client devices for a web resource comprising web code is obtained. The web resource is hosted by a first web server system. For a first client device of the plurality of client devices, instrumentation code is served. The instrumentation code is configured to execute on the first client device to monitor execution of the web code of the web resource at the first client device. One or more responses generated by the instrumentation code at the first client device are received from the first client device. The one or more responses are based one or more interactions with the web code at the first client device.

Abstract: A computer-implemented method includes receiving, at a primary security sub-system, code to be served from a web server system to one or more computing devices; forwarding a representation of the code to a secondary security sub-system that is remote from the primary security sub-system; receiving, from the secondary sub-system and in response to the forwarding, a template created from analysis of the representation of the code that indicates changes to be made to the code and locations of the changes; and using the template to recode the code, by the primary security sub-system, before serving the code to the one or more computing devices.

Abstract: In one implementation, a computer-implemented method can identify abnormal computer behavior. The method can receive, at a computer server subsystem and from a web server system, computer code to be served in response to a request from a computing client over the internet. The method can also modify the computer code to obscure operational design of the web server system that could be determined from the computer code, and supplement the computer code with instrumentation code that is programmed to execute on the computing client. The method may serve the modified and supplemented computer code to the computing client.

Abstract: A computer-implemented method for identifying abnormal computer behavior includes receiving, at a computer server subsystem, data that characterizes subsets of particular document object models for web pages rendered by particular client computers; identifying clusters from the data that characterize the subsets of the particular document object models; and using the clusters to identify alien content on the particular client computers, wherein the alien content comprises content in the document object models that is not the result of content that is the basis of the document object model served.

Abstract: A computer-implemented method for identifying abnormal computer behavior includes receiving, at a computer server subsystem, data that characterizes subsets of particular document object models for web pages rendered by particular client computers; identifying clusters from the data that characterize the subsets of the particular document object models; and using the clusters to identify alien content on the particular client computers, wherein the alien content comprises content in the document object models that is not the result of content that is the basis of the document object model served.

Abstract: A computer-implemented method involves identifying an initial element for serving by a web server system to a client device and recoding the element by creating a plurality of different elements that each represent a portion of the initial element. The different elements are then served in place of the initial element. A response is received form the client device and has portions that correspond to the different elements, and a combined response is created by combining the received portions in a manner that corresponds to a manner in which the initial element was recoded to create the plurality of different elements.

Abstract: This document describes, among other things, a computer-implemented method for improving the security of one or more computing systems. The method can include receiving, at a computing system, first code that defines at least a portion of an electronic resource that is to be served to a client computing device. The method can include generating code that defines a challenge to be solved by the client computing device, in which the code is arranged to cause the client computing device to determine values for one or more parameters that comprise a solution to the challenge, and the values for the one or more parameters that comprise the solution to the challenge may be required for the client computing device to make valid requests to initiate one or more web-based transactions. The computing system can determine whether particular values for the parameters comprise a valid solution to the challenge.

Abstract: A computer-implemented method for coordinating content transformation includes receiving, at a computer server subsystem and from a web server system, computer code to be served in response to a request from a computing client over the internet; modifying the computer code to obscure operation of the web server system that could be determined from the computer code; generating transformation information that is needed in order to reverse the modifications of the computer code to obscure the operation of the web server system; and serving to the computing client the modified code and the reverse transformation information.

Abstract: In some implementations, a computer system for obfuscating text in an electronic document can include an analysis module, a font data repository, a re-coding module, and a data interface. The analysis module is operable to identify strings of text from an electronic document. The font data repository can include one or more character maps that correlate, for each character map in the one or more character maps, a first set of characters with a respective different second set of characters. The re-coding module can generate a re-coded document by re-mapping, using a particular one of the one or more character maps, the identified strings of text into corresponding obfuscated strings of text, and by replacing the identified strings of text with the corresponding obfuscated strings of text from the electronic document. The data interface can transmit the re-coded document to a client computing device.

Abstract: In one implementation, a computer-implemented method can identify abnormal computer behavior. The method can receive, at a computer server subsystem and from a web server system, computer code to be served in response to a request from a computing client over the internet. The method can also modify the computer code to obscure operational design of the web server system that could be determined from the computer code, and supplement the computer code with instrumentation code that is programmed to execute on the computing client. The method may serve the modified and supplemented computer code to the computing client.

Abstract: A computer-implemented method for identifying abnormal computer behavior includes receiving, at a computer server subsystem, data that characterizes subsets of particular document object models for web pages rendered by particular client computers; identifying clusters from the data that characterize the subsets of the particular document object models; and using the clusters to identify alien content on the particular client computers, wherein the alien content comprises content in the document object models that is not the result of content that is the basis of the document object model served.