Systems and methods for implementing a secure user interface

A computing device, comprising:

• a display device;
• and
• a processor coupled to the display device and configured to execute instructions within a secure execution environment and a normal execution environment, wherein the processor is configured to execute processor-executable instructions to perform operations comprising:
• determining, by a secure application running in a secure execution environment of the computing device, that code for generating a data input element of a user interface of a client application running in the normal execution environment includes code for generating a vulnerable data input element that allows freeform data entry;
• preventing, by the secure application, execution of the code for generating the vulnerable data input element by the client application in response to determining, by the secure application, that the code for generating the data input element includes the code for generating the vulnerable data input element;
• generating in the secure execution environment by the secure application a secure user interface display portion comprising a secure user interface element that is based on the data input element;
• generating a non-secure display portion by the client application in the normal execution environment;
• combining the secure user interface display portion and the non-secure display portion into a combined display;
• and
• presenting the combined display on the display device.

A non-transitory processor-readable storage medium having stored thereon processor-executable instructions configured to cause a processor of a computing device to perform operations comprising:

• determining, by a secure application running in a secure execution environment of the computing device, that code for generating a data input element of a user interface of a client application running in the normal execution environment includes code for generating a vulnerable data input element that allows freeform data entry;
• preventing, by the secure application, execution of the code for generating the vulnerable data input element by the client application in response to determining, by the secure application, that the code for generating the data input element includes the code for generating the vulnerable data input element;
• generating in the secure execution environment by the secure application a secure user interface display portion comprising a secure user interface element that is based on the data input element;
• generating a non-secure display portion by the client application in the normal execution environment;
• combining the secure user interface display portion and the non-secure display portion into a combined display;
• and
• presenting the combined display on a display device.

A computing device, comprising:

• a display device;
• means for determining, by a secure application running in a secure execution environment of the computing device, that code for generating a data input element of a user interface of a client application running in the normal execution environment includes code for generating a vulnerable data input element that allows freeform data entry;
• means for preventing, by the secure application, execution of the code for generating the vulnerable data input element by the client application in response to determining, by the secure application, that the code for generating the data input element includes the code for generating the vulnerable data input element;
• means for generating in the secure execution environment by the secure application a secure user interface display portion comprising a secure user interface element that is based on the data input element;
• means for generating a non-secure display portion by the client application in the normal execution environment of the computing device;
• means for combining the secure user interface display portion and the non-secure display portion into a combined display;
• and
• means for presenting the combined display on the display device.