METHOD AND SYSTEM FOR RENDERING A STOLEN MOBILE COMMUNICATIONS DEVICE INOPERATIVE

• US 20140372743A1
• Filed: 06/05/2014
• Published: 12/18/2014
• Est. Priority Date: 06/12/2013
• Status: Active Grant

• Current Assignee: F-Secure Corporation (F-Secure Oyj)
• Original Assignee: Lookout Incorporated
• Inventors: Buck, Brian James, Rogers, Marc William
• Granted Patent: US 10,084,603 B2
• Time in Patent Office: Days
• US Class Current: 713/2
• CPC Class Codes: G06F 21/575 Secure boot
• CPC Class Codes: G09C 1/00 Apparatus or methods whereby a given sequence of signs, e.g. an intelligible text, is transformed into an unintelligible sequence of signs by transposing the signs or groups of signs or by replacing them by others according to a predetermined system cryptographic typewriters G09C3/00
• CPC Class Codes: H04L 2209/127 Trusted platform modules [TPM]
• CPC Class Codes: H04L 2209/80 Wireless network architectures or network communication protocols for wireless network security H04W12/00
• CPC Class Codes: H04L 9/088 Usage controlling of secret information, e.g. techniques for restricting cryptographic keys to pre-authorized uses, different access levels, validity of crypto-period, different key- or password length, or different strong and weak cryptographic algorithms network architectures or network communication protocols for using time-dependent keys in a packet data network H04L63/068
• CPC Class Codes: H04L 9/3234 involving additional secure or trusted devices, e.g. TPM, smartcard, USB or software token network architectures or network communication protocols for supporting authentication of entities using an additional device in a packet data network H04L63/0853
• CPC Class Codes: H04W 12/12 Detection or prevention of fraud
• CPC Class Codes: H04W 12/126 Anti-theft arrangements, e.g. protection against subscriber identity module [SIM] cloning

Abstract

A method and system for rendering a stolen mobile communications device inoperative is presented. A determination that the mobile communications device is in a first state is made at a security component on the mobile communications device. A removal of a cryptographic key is affected at the security component on the mobile communications device.

Claims

1. A method comprising:

determining, at a security component on a mobile communications device, that the mobile communications device is in a first state; and

causing, at the security component, a removal of a cryptographic key on the mobile communications device.

2. The method of claim 1, wherein the first state is an indication that the mobile communications device is not in the possession of an authorized user.

3. The method of claim 1, wherein the cryptographic key on the mobile communications device is a cryptographic key of a bootloader program.

4. The method of claim 3, wherein the removal of the cryptographic key of the bootloader program causes, when a boot sequence of the mobile communications device detects an absence of the cryptographic key, the mobile communications device to boot into a specific mode.

5. The method of claim 4, further comprising, when the mobile communications device is determined to be in a second state indicating that the mobile communications device is in the possession of an authorized user, receiving the cryptographic key from the server.

6. The method of claim 5, wherein the cryptographic key is stored in one of a Trusted Platform Module (TPM) or a separate hardware component that supports a command to destroy the cryptographic keys.

7. The method of claim 4, wherein causing the mobile communications device to boot into the specific mode comprises causing the mobile communications device to boot into a limited kernel.

8. The method of claim 7, wherein booting into the limited kernel causes the mobile communications device to communicate with a server to report one of a location or a contextual information of the mobile communications device.

9. The method of claim 1, wherein the cryptographic key is stored in one of a Trusted Platform Module (TPM) or a separate hardware component that supports a command to destroy the cryptographic keys.

10. The method of claim 3, further comprising initiating one of a reboot sequence or a power off sequence, upon causing the removal of the cryptographic key of the bootloader program on the mobile communications device.

11. The method of claim 3, wherein the cryptographic key of the bootloader program on the mobile communications device comprises information unique to the mobile communications device.

12. The method of claim 11, wherein the information unique to the mobile communications device is an International Mobile Station Equipment Identity (IMEI) number.

13. The method of claim 1, wherein the cryptographic key on the mobile communications device is a cryptographic key used to decrypt encrypted device storage contents.

14. A method comprising:

determining, at a security component on a mobile communications device, that the mobile communications device is not in the possession of an authorized user;

when the mobile communications device is determined to not be in the possession of an authorized user, receiving, from a server and at the security component, a cryptographic key;

encrypting, at the security component, device storage contents with the cryptographic key; and

after encrypting the device storage contents, causing, at the security component, a removal of the cryptographic key on the mobile communications device.

15. The method of claim 14, wherein a copy of the cryptographic key is retrievable from the server by a security program operating on the mobile communications device, the cryptographic key being retrievable when the server determines that the security program fulfills predetermined security privileges criteria.

16. The method of claim 14, wherein the cryptographic key received from the server is not stored on the mobile communications device.

17. A non-transitory computer-readable medium encoded with a plurality of instructions which, when executed by a processor, cause the processor to perform a method comprising:

receiving, at a server, an indication that a mobile communications device is not in the possession of an authorized user;

sending, from the server, a first command for the mobile communications device to encrypt data stored on the mobile communications device using a cryptographic key from the server; and

upon receiving from the mobile communications device confirmation that the data stored has been encrypted, sending, from the server, a second command for the mobile communications device to remove the cryptographic key.

18. The non-transitory computer-readable medium of claim 17, further comprising instructions for:

upon receiving from the mobile communications device an indication that the cryptographic key has been removed, sending, from the server, a third command for the mobile communications device to initiate one of a reboot sequence or a power off sequence.

19. The non-transitory computer-readable medium of claim 18, wherein the instructions for sending the second command for removal of the cryptographic key causes, when a boot sequence of the mobile communications device detects an absence of the cryptographic key, the mobile communications device to boot into a specific mode.

20. The non-transitory computer-readable medium of claim 19, wherein the booting into the specific mode causes the mobile communications device to communicate with the server to report one of a location or a contextual information.

21. The non-transitory computer-readable medium of claim 17, further comprising instructions for:

receiving, at the server, an indication that the mobile communications device is in a second state indicating that the mobile communications device is in the possession of an authorized user;

sending, upon receiving the indication that the mobile communications device is in the second state, a copy of the cryptographic key from the server to the mobile communications device.