Computer-implemented method for mitigating anomalous activity

1 . A computer-implemented method for mitigating anomalous activity in an embedded computer system, the embedded computer system including a plurality of communicably coupled embedded processing elements, the method comprising the following steps:

detecting, by an embedded processing element of the plurality of the embedded processing elements, a transmission of an anomalous message in the embedded computer system, the embedded computer system transitioning from a normal operation to an emergency operation in response to the detection of the transmission of the anomalous message;

transmitting, by the embedded processing element upon the detection of the transmission of the anomalous message, at least one notification to a further plurality of the embedded processing elements in the embedded computer system, wherein a portion of the at least one notification is encrypted using a cryptographic key, and wherein the cryptographic key is a dedicated emergency key used only during the emergency operation and not used during the normal operation of the embedded computer system; and

by at least one embedded processing element of the further plurality of the embedded processing elements:

receiving the at least one notification;

identifying, at the at least one embedded processing element, that the at least one notification has been encrypted using the dedicated emergency key; and

reconfiguring the at least one embedded processing element from a first mode into a second mode, wherein the at least one embedded processing element presents a reduced functionality to the embedded computer system in the second mode.

2 . The computer-implemented method according to claim 1 , wherein the transmission of an anomalous message in the embedded computer system is detected by one or a combination of: (i) detection of an anomalous call to a decoy application programming interface of an application hosted by at least one of the embedded processing elements, or (ii) detection of an anomalous communication to a decoy embedded processing element, or (iii) detection of an anomalous message via packet inspection in the embedded computer system.

3 . The computer-implemented method according to claim 1 , further comprising:

for each embedded processing element included in a first subset of the plurality of embedded processing elements, the reconfiguring into a reduced functionality includes suspending operation of each embedded processing element of the first subset of the plurality of embedded processing elements, or suspending at least one function provided by each embedded processing element in the first subset.

4 . The computer-implemented method according to claim 1 , further comprising:

for each embedded processing element included in a second subset of the plurality of embedded processing elements, the reconfiguring into a reduced functionality includes suspending at least one function provided by each embedded processing element in the second subset.

5 . The computer-implemented method according to claim 4 , further comprising:

for at least one embedded processing element in the second subset of the plurality of embedded processing elements:

upon reconfiguration into the second mode, ignoring, at the at least one embedded processing element in the second subset of the plurality of embedded processing elements, all messages received by the at least one processing embedded element in the second subset of the plurality of embedded processing elements that do not contain a cryptographic key associated with the notification.

6 . The computer-implemented method according to claim 1 , further comprising:

upon reconfiguration into the second mode:

initiating at least one trusted execution environment associated with at least one embedded processing element, wherein the at least one trusted execution environment comprises a segregated area of a CPU;

receiving, at the at least one embedded processing element, a message; and

processing the message within the trusted execution environment, wherein the message is decrypted using a pre-shared cryptographic key.

7 . The computer-implemented method according to claim 1 , further comprising:

upon reconfiguration into the second mode:

generating, using at least one embedded processing element, a message to be transmitted to a further embedded processing element included in the plurality of embedded processing elements;

obfuscating a portion of the message to be transmitted to the further embedded processing element; and

transmitting the message comprising the obfuscated portion to the further embedded processing element.

8 . The computer-implemented method according to claim 1 , wherein the embedded computer system is a vehicle control system.

9 . The computer-implemented method according to claim 8 , wherein upon reconfiguring the at least one embedded processing element from the first mode to the second mode, at least one processing element transmits a notification message reporting the detection of the anomalous message to a driver of the vehicle and/or a vehicle fleet monitoring centre.

10 . The computer-implemented method according to claim 8 , wherein, upon reconfiguring the at least one embedded processing element from the first mode to the second mode, the reduced functionality of the at least one embedded processing element enables the vehicle to drive with a reduced or minimal feature set.

11 . The computer-implemented method according to claim 1 , further comprising:

transmitting at least one reset notification to a plurality of the embedded processing elements in the embedded computer system; and

at each embedded processing element, reconfiguring the embedded processing element from the second mode to the first mode upon reception, at the embedded processing element, of the reset notification.

12 . An embedded computer system, comprising:

a plurality of embedded processing elements;

an intrusion detection system; and

a communications network configured to communicably couple the plurality of embedded processing elements and the intrusion detection system;

wherein at least one processing element of the plurality of embedded processing elements and/or the intrusion detection system is configured to detect a transmission of an anomalous message in the embedded computer system, the embedded computer system transitioning from a normal operation to an emergency operation in response to the detection of the transmission of the anomalous message, and, upon the detection of the anomalous message in the embedded computer system, to transmit at least one notification to a further plurality of the embedded processing elements in the embedded computer system, wherein the at least one notification is encrypted using a cryptographic key, and wherein the cryptographic key is a dedicated emergency key used only during the emergency operation and not used during the normal operation of the embedded computer system; and

wherein at least one processing element of the further plurality of processing elements is configured to receive the at least one notification, to identify that the at least one notification has been encrypted using the dedicated emergency key, and to reconfigure the at least one processing element from a first mode into a second mode, wherein the at least one processing element presents a reduced functionality to the embedded computer system in the second mode.

13 . A vehicle, comprising:

an embedded computer system, including:

a plurality of embedded processing elements;

an intrusion detection system, and

a communications network configured to communicably couple the plurality of embedded processing elements and the intrusion detection system,

wherein at least one processing element of the plurality of embedded processing elements and/or the intrusion detection system is configured to detect a transmission of an anomalous message in the embedded computer system, the embedded computer system transitioning from a normal operation to an emergency operation in response to the detection of the transmission of the anomalous message, and, upon the detection of the anomalous message in the embedded computer system, to transmit at least one notification to a further plurality of the embedded processing elements in the embedded computer system, wherein the at least one notification is encrypted using a cryptographic key, and wherein the cryptographic key is a dedicated emergency key used only during the emergency operation and not used during the normal operation of the embedded computer system, and

wherein at least one processing element of the further plurality of processing elements is configured to receive the at least one notification, to identify that the at least one notification has been encrypted using the dedicated emergency key, and to reconfigure the at least one processing element from a first mode into a second mode, wherein the at least one processing element presents a reduced functionality to the embedded computer system in the second mode.

14 . The vehicle according to claim 13 , wherein, upon reconfiguration of the at least one processing element of the embedded computer system from the first mode into the second mode, the at least one processing element presents a reduced functionality to the embedded computer system in the second mode, thus causing the vehicle to operate with a reduced feature set.

15 . A non-transitory computer-readable medium on which is stored machine readable instructions for mitigating anomalous activity in an embedded computer system, the embedded computer system including a plurality of communicably coupled embedded processing elements, the instructions, when executed by at least one of the embedded processing elements, causing the at least one of the embedded processing elements to perform the following steps:

detecting, by an embedded processing element of the plurality of embedded processing elements, a transmission of an anomalous message in the embedded computer system, the embedded computer system transitioning from a normal operation to an emergency operation in response to the detection of the transmission of the anomalous message;

transmitting, by the embedded processing element upon the detection of the transmission of the anomalous message, at least one notification to a further plurality of the embedded processing elements in the embedded computer system, wherein a portion of the at least one notification is encrypted using a cryptographic key, and wherein the cryptographic key is a dedicated emergency key used only during the emergency operation and not used during the normal operation of the embedded computer system; and

by at least one embedded processing element of the further plurality of embedded processing elements:

receiving the at least one notification;

identifying, at the at least one embedded processing element, that the at least one notification has been encrypted using the dedicated emergency key; and

reconfiguring the at least one embedded processing element from a first mode into a second mode, wherein the at least one embedded processing element presents a reduced functionality to the embedded computer system in the second mode.