Method and system for responding to an unauthorized action on a mobile communications device

• US 10,511,442 B2
• Filed: 08/23/2018
• Issued: 12/17/2019
• Est. Priority Date: 06/12/2013
• Status: Active Grant

• Current Assignee: F-Secure Corporation (F-Secure Oyj)
• Original Assignee: Lookout Incorporated
• Inventors: Rogers, Marc William, Buck, Brian James
• Primary Examiner(s): Abbaszadeh, Jaweed A
• Assistant Examiner(s): Sampath, Gayathri
• Application Number:
  US16/110,963
• Publication Number:
  US 20190013947A1
• Time in Patent Office: 481 Days
• 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

In a method and system for responding to an unauthorized action on a mobile communications device, a cryptographic key is destroyed. The destruction of the cryptographic key is followed by initiating a boot sequence at the mobile communications device where the device is booted into a kernel that restricts operation of the mobile communications device to communications with a server.

Claims

1. A method comprising:

determining, by an autonomous security component of a mobile communications device, that the mobile communications device is in a first state, the first state being an indication that an unauthorized action has been attempted on the mobile communications device, wherein the autonomous security component is preloaded on a system partition of an internal memory of a mobile communications device where an operating system is stored, wherein the autonomous security component is configured to persist after a factory reset of the mobile communications device, and wherein the autonomous security component is separate from the operating system;

in response to the determination that the mobile communications device is in the first state, initiating and causing, by the autonomous security component, a destruction of a cryptographic key of a bootloader from a key store on the mobile communications device;

upon initiating and causing the destruction of the cryptographic key of the bootloader, initiating, by the autonomous security component, a boot sequence at the mobile communications device; and

during the boot sequence at the mobile communications device after the destruction of the cryptographic key, booting the mobile communications device into a kernel that restricts operation of the mobile communications device so that the mobile communications device can only communicate with a single server;

(i) to report at least one of;

a mobile communications device location, or mobile communications device contextual information; and

(ii) to receive a re-enablement cryptographic key from the single server.

2. The method of claim 1, wherein booting the mobile communications device into a kernel that restricts operation of the mobile communications device includes booting into a specific mode.

3. The method of claim 2, further comprising:

determining, at the autonomous security component on the mobile communications device when the mobile communications device is booted into the specific mode, that the mobile communications device is in a second state, the second state being an indication that the mobile communications device is in possession of an authorized user, and

when the mobile communications device is determined to be in the second state indicating that the mobile communications device is in possession of an authorized user, receiving, at the autonomous security component on the mobile communications device, the re-enablement cryptographic key from the single server to replace the destroyed cryptographic key from the key store.

4. The method of claim 3, wherein the re-enablement cryptographic key received from the single server is stored by the autonomous security component in one of a Trusted Platform Module (TPM) or a separate hardware component that supports a command to cause the destruction of the cryptographic key.

5. The method of claim 1 further comprising receiving, at the autonomous security component, a re-enablement cryptographic key from the single server, wherein the re-enablement cryptographic key received from the single server is stored by the autonomous security component in one of a Trusted Platform Module (TPM) or a separate hardware component that supports a command to cause the destruction of the cryptographic key.

6. The method of claim 1, wherein the initiating, by the autonomous security component, a boot sequence at the mobile communications device includes initiating one of a reboot sequence or a power-off sequence.

7. The method of claim 1, wherein the cryptographic key of the bootloader on the mobile communications device comprises information unique to the mobile communications device.

8. The method of claim 7, wherein the information unique to the mobile communications device is an International Mobile Station Equipment Identity (IMEI) number.

9. 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.

10. The method of claim 1, wherein the re-enablement cryptographic key is retrievable from the single server by a security program operating on the mobile communications device, the re-enablement cryptographic key being retrievable when the single server determines that the security program fulfills predetermined security privileges criteria.

11. A method comprising:

determining, by an autonomous security component of a mobile communications device, that an unauthorized action has been attempted on the mobile communications device, wherein the autonomous security component is preloaded on a system partition of an internal memory of a mobile communications device where an operating system is stored, wherein the autonomous security component is configured to persist after a factory reset of the mobile communications device, and wherein the autonomous security component is separate from the operating system;

when the determination is that an unauthorized action has been attempted on the mobile communications device, receiving, from a single server and at the autonomous security component, a first cryptographic key;

encrypting, by the autonomous security component, device storage contents with the first cryptographic key;

after encrypting the device storage contents, initiating and causing, by the autonomous security component, a destruction of a second cryptographic key from a key store on the mobile communications device, the second cryptographic key being a cryptographic key of a bootloader;

upon initiating and causing the destruction of the second cryptographic key, initiating, by the autonomous security component, a boot sequence at the mobile communications device; and

during the boot sequence at the mobile communications device after the destruction of the second cryptographic key, booting the mobile communications device into a kernel that restricts operation of the mobile communications device so that the mobile communications device can only communicate with the single server;

(i) to report at least one of;

a mobile communications device location, or mobile communications device contextual information; and

(ii) to receive a re-enablement second cryptographic key from the single server.

12. The method of claim 11, wherein the re-enablement second cryptographic key is retrievable from the single server by a security program operating on the mobile communications device, the re-enablement second cryptographic key being retrievable when the single server determines that the security program fulfills predetermined security privileges criteria.

13. The method of claim 11, wherein booting the mobile communications device into a kernel that restricts operation of the mobile communications device includes booting into a specific mode.

14. The method of claim 13, further comprising:

determining, at the autonomous security component on the mobile communications device when the mobile communications device is booted into the specific mode, that the mobile communications device is in a second state, the second state being an indication that the mobile communications device is in possession of an authorized user, and

when the mobile communications device is determined to be in the second state indicating that the mobile communications device is in possession of an authorized user, receiving, at the autonomous security component on the mobile communications device, the re-enablement second cryptographic key from the single server to replace the destroyed second cryptographic key from the key store.

15. 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 an unauthorized action has been attempted on a mobile communications device;

sending, from the server, a first command for a security component of the mobile communications device, the first command directing the security component to encrypt data stored on the mobile communications device using a first cryptographic key from the server, wherein the security component is preloaded on a system partition of an internal memory of the mobile communications device where an operating system is stored, wherein the security component is configured to persist after a factory reset, and wherein the security component is separate from the operating system;

upon the server receiving, from the security component of the mobile communications device, confirmation that the data stored has been encrypted, sending, from the server, a second command for the security component of the mobile communications device to cause a destruction of a second cryptographic key from a key store on the mobile communications device, the second cryptographic key being a cryptographic key of a bootloader, wherein, upon causing the destruction of the second cryptographic key of the bootloader, the security component autonomously initiates a boot sequence at the mobile communications device; and

during the boot sequence at the mobile communications device after the destruction of the second cryptographic key, booting the mobile communications device into a kernel that restricts operation of the mobile communications device so that the mobile communications device can only communicate with the server;

(i) to report at least one of;

a mobile communications device location, or mobile communications device contextual information; and

(ii) to receive a re-enablement second cryptographic key from the server.

16. The non-transitory computer-readable medium of claim 15, wherein the security component autonomously initiating a boot sequence at the mobile communications device includes the security component of the mobile communications device initiating one of a reboot sequence or a power-off sequence.

17. The non-transitory computer-readable medium of claim 15, 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 possession of an authorized user, after having been booted into the kernel that restricts operation of the mobile communications device; and

sending, upon receiving the indication that the mobile communications device is in the second state, the re-enablement second cryptographic key from the server to the mobile communications device.

18. The non-transitory computer-readable medium of claim 15, wherein booting the mobile communications device into a kernel that restricts operation of the mobile communications device includes booting into a specific mode.

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

determining, at the server, when the mobile communications device is booted into the specific mode, that the mobile communications device is in a second state, the second state being an indication that the mobile communications device is in possession of an authorized user, and

when the mobile communications device is determined to be in the second state indicating that the mobile communications device is in possession of an authorized user, sending, by the single server, the re-enablement second cryptographic key to replace the destroyed second cryptographic key from the key store.

20. The non-transitory computer-readable medium of claim 15, further comprising instructions for:

determining, at the server, that a security program on the mobile communications device fulfills predetermined security privileges criteria; and

when the server determines that the security program fulfills predetermined security privileges criteria, making the re-enablement second cryptographic key retrievable from the single server by the security program.