Side-Channel Attack

Threat actors may use a side-channel attack attempts to gather information by measuring or exploiting indirect effects of the spacecraft. Information within the spacecraft can be extracted through these side-channels in which sensor data is analyzed in non-trivial ways to recover subtle, hidden or unexpected information. A series of measurements of a side-channel constitute an identifiable signature which can then be matched against a signature database to identify target information, without having to explicitly decode the side-channel.

ID: EXF-0002
Related Aerospace Threat IDs:  SV-AC-5 | SV-CF-1 | SV-CF-2
Created: 2022/10/19
Last Modified: 2022/12/08


ID Name Description NIST Rev5
CM0002 COMSEC A component of cybersecurity to deny unauthorized persons information derived from telecommunications and to ensure the authenticity of such telecommunications. COMSEC includes cryptographic security, transmission security, emissions security, and physical security of COMSEC material. It is imperative to utilize secure communication protocols with strong cryptographic mechanisms to prevent unauthorized disclosure of, and detect changes to, information during transmission. Systems should also maintain the confidentiality and integrity of information during preparation for transmission and during reception. Spacecraft should not employ a mode of operations where cryptography on the TT&C link can be disabled (i.e., crypto-bypass mode). The cryptographic mechanisms should identify and reject wireless transmissions that are deliberate attempts to achieve imitative or manipulative communications deception based on signal parameters. AC-17(1) AC-17(10) AC-17(10) AC-17(2) AC-18(1) AC-2(11) AC-3(10) IA-4(9) IA-5 IA-5(7) IA-7 SA-8(18) SA-9(6) SC-10 SC-12 SC-12(1) SC-12(2) SC-12(3) SC-12(6) SC-13 SC-13(1) SC-13(2) SC-16(3) SC-28(1) SC-28(3) SC-7 SC-7(10) SC-7(11) SC-7(18) SC-7(5) SI-10 SI-10(3) SI-10(5) SI-10(6) SI-19(4) SI-3(8)
CM0073 Traffic Flow Analysis Defense Utilizing techniques to assure traffic flow security and confidentiality to mitigate or defeat traffic analysis attacks or reduce the value of any indicators or adversary inferences. This may be a subset of COMSEC protections, but the techniques would be applied where required to links that carry TT&C and/or data transmissions (to include on-board the spacecraft) where applicable given value and attacker capability. Techniques may include but are not limited to methods to pad or otherwise obfuscate traffic volumes/duration and/or periodicity, concealment of routing information and/or endpoints, or methods to frustrate statistical analysis. SC-8 SI-4(15)
CM0003 TEMPEST The spacecraft should protect system components, associated data communications, and communication buses in accordance with TEMPEST controls to prevent side channel / proximity attacks. Encompass the spacecraft critical components with a casing/shielding so as to prevent access to the individual critical components. PE-19 PE-19(1) PE-21
CM0050 On-board Message Encryption In addition to authentication on-board the spacecraft bus, encryption is also recommended to protect the confidentiality of the data traversing the bus. AC-4 AC-4(23) AC-4(24) AC-4(26) AC-4(31) AC-4(32) SA-8(18) SA-8(9) SA-9(6) SC-13 SC-16(2) SC-16(3) SI-19(4) SI-4(10) SI-4(25)
CM0062 Dummy Process - Aggregator Node According to Securing Sensor Nodes Against Side Channel Attacks, it is practically inefficient to prevent adversaries from identifying aggregator nodes in a network (i.e., constellation) because camouflaging traffic in sensor networks is power intensive. Consequently, focus on preventing adversaries from identifying valid aggregation cycles of aggregator nodes. One solution to counter such attacks is to have each aggregator node execute dummy operations that resemble the average power consumption curve observed during the normal operation of the aggregator node. Apart from simulating the power consumption of a genuine process execution, the two necessities that the execution of the dummy process must incorporate to be successful in thwarting the accumulation phase are to use a different dummy execution process each time or have a low repetition rate. This should help prevent the attacker from finding a pattern that would differentiate the execution of a dummy process from the normal execution of an aggregator node. The second requirement relates to the timing of the execution of the dummy process. Depending on whether there is a pattern to the timing of the execution of a dummy process, a threat actor may be able to identify and disregard the dummy process. For example, if a threat actor is capable of identifying the presence or absence of a radio frequency transmission, the attacker can disregard any power consumption curve computed during the absence of transmission signal. Similarly, if the dummy process is not executed every time the aggregator node receives a transmission, the attacker will be able to identify invalid transmission. Hence, to ensure the effectiveness of this scheme, the dummy process must be executed each time the aggregator receives a transmission as well as randomly during idle periods. The advantage of incorporating dummy processes in an aggregator is to minimize the ease of identifying transmission flow in a sensor network that can be used to identify the base station of the sensor network, which could be highly confidential in critical applications. PE-19 PE-19(1)
CM0057 Tamper Resistant Body Using a tamper resistant body can increase the one-time cost of the sensor node but will allow the node to conserve the power usage when compared with other countermeasures. PE-19 PE-19(1)
CM0058 Power Randomization Power randomization is a technique in which a hardware module is built into the chip that adds noise to the power consumption. This countermeasure is simple and easy to implement but is not energy efficient and could be impactful for size, weight, and power which is limited on spacecraft as it adds to the fabrication cost of the device. PE-19 PE-19(1)
CM0059 Power Consumption Obfuscation Design hardware circuits or perform obfuscation in general that mask the changes in power consumption to increase the cost/difficulty of a power analysis attack. This will increase the cost of manufacturing sensor nodes. PE-19 PE-19(1)
CM0060 Secret Shares Use of secret shares in which the original computation is divided probabilistically such that the power subset of shares is statistically independent. One of the major drawbacks of this solution is the increase in the power consumption due to the number of operations that are almost doubled. PE-19 PE-19(1)
CM0061 Power Masking Masking is a scheme in which the intermediate variable is not dependent on an easily accessible subset of secret key. This results in making it impossible to deduce the secret key with partial information gathered through electromagnetic leakage. PE-19 PE-19(1)
CM0063 Increase Clock Cycles/Timing Use more clock cycles such that branching does not affect the execution time. Also, the memory access times should be standardized to be the same over all accesses. If timing is not mission critical and time is in abundance, the access times can be reduced by adding sufficient delay to normalize the access times. These countermeasures will result in increased power consumption which may not be conducive for low size, weight, and power missions. PE-19 PE-19(1)
CM0064 Dual Layer Protection Use a dual layered case with the inner layer a highly conducting surface and the outer layer made of a non-conducting material. When heat is generated from internal computing components, the inner, highly conducting surface will quickly dissipate the heat around. The outer layer prevents accesses to the temporary hot spots formed on the inner layer. PE-19 PE-19(1)
CM0071 Communication Physical Medium Establish alternate physical medium for networking based on threat model/environment. For example, fiber optic cabling is commonly perceived as a better choice in lieu of copper for mitigating network security concerns (i.e., eavesdropping / traffic flow analysis) and this is because optical connections transmit data using light, they don’t radiate signals that can be intercepted. PE-4 SC-8 SC-8(5)