Patent attributes
Techniques for enhancing the security of a communication device may include providing an application agent that executes in a trusted execution environment of the communication device, and a transaction application that executes in a normal application execution environment of the communication device. The application agent may receive, from the application, a limited-use key (LUK) generated by a remote computer, and store the LUK in a secure storage of the trusted execution environment. When the application agent receives a request to conduct a transaction from the application executing in the normal execution environment, the application agent may generate a transaction cryptogram using the LUK, and provides the transaction cryptogram to an access device.