On the Security of Carrier Phase-based Ranging Hildur Olafsdottir, - PowerPoint PPT Presentation

On the Security of Carrier Phase-based Ranging Hildur Olafsdottir, Aanjhan Ranganathan, Srdjan Capkun

Importance of Secure Proximity Verification Aanjhan Ranganathan On the Security of Carrier Phase-based Ranging 2

Importance of Secure Proximity Verification Aanjhan Ranganathan On the Security of Carrier Phase-based Ranging 2

Importance of Secure Proximity Verification Aanjhan Ranganathan On the Security of Carrier Phase-based Ranging 2

Importance of Secure Proximity Verification Aanjhan Ranganathan On the Security of Carrier Phase-based Ranging 2

Importance of Secure Proximity Verification Distance is determined using a variety of methods (e.g., based on received signal strength , time of flight etc.) Aanjhan Ranganathan On the Security of Carrier Phase-based Ranging 2

Estimating Distance t tof t p d d = c * (t tof - t p ) / 2 Received Signal Strength (RSS) Time of Flight (ToF) Physical-layer Techniques for Secure Proximity Verification & Localization 3

Attacks on Proximity Systems Aanjhan Ranganathan On the Security of Carrier Phase-based Ranging 4

Attacks on Proximity Systems Aanjhan Ranganathan On the Security of Carrier Phase-based Ranging 4

Attacks on Proximity Systems Aanjhan Ranganathan On the Security of Carrier Phase-based Ranging 4

Attacks on Proximity Systems Aanjhan Ranganathan On the Security of Carrier Phase-based Ranging 4

Attacks on Proximity Systems Aanjhan Ranganathan On the Security of Carrier Phase-based Ranging 4

Attacks on Proximity Systems No knowledge of the data exchanged is required! Independent of cryptographic primitives Aanjhan Ranganathan On the Security of Carrier Phase-based Ranging 4

Multi-carrier Phase Ranging • Cost optimised solution for proximity-based applications • Low-hardware complexity, low-power consumption, high precision • Compliant with prominent standards such as WiFi, ZigBee • Localization schemes* leveraging signal phase information are increasingly becoming popular ‣ 802.11, NB-IoT, LoRa, 5G networks * Vasisht, Deepak, Swarun Kumar, and Dina Katabi. "Decimeter-Level Localization with a Single WiFi Access Point." NSDI 2016. * Xiong, J., Sundaresan, K., Jamieson, K. “Tonetrack: Leveraging frequency-agile radios for time-based indoor wireless localization.” MobiCom 2015. * Exel, R. “Carrier-based ranging in ieee 802.11 wireless local area networks.” IEEE Wireless Communications and Networking Conference (WCNC) 2013. Aanjhan Ranganathan On the Security of Carrier Phase-based Ranging 5

Motivation • Implications of distance modification attacks are significant ‣ loss of property to even human life (e.g., IMD access control) • Security of multi-carrier phase ranging has not be analysed yet. ‣ number of prior works on other prominent ranging systems* Aanjhan Ranganathan On the Security of Carrier Phase-based Ranging 6

Contributions Aanjhan Ranganathan On the Security of Carrier Phase-based Ranging 7

Contributions • Investigate the vulnerability of carrier phase-based ranging system to distance modification attacks ‣ focus on distance reduction attacks ‣ no knowledge of the implemented cryptographic primitive (if any) required Aanjhan Ranganathan On the Security of Carrier Phase-based Ranging 7

Contributions • Investigate the vulnerability of carrier phase-based ranging system to distance modification attacks ‣ focus on distance reduction attacks ‣ no knowledge of the implemented cryptographic primitive (if any) required • Three different attack realisations (varying attacker complexity) Aanjhan Ranganathan On the Security of Carrier Phase-based Ranging 7

Contributions • Investigate the vulnerability of carrier phase-based ranging system to distance modification attacks ‣ focus on distance reduction attacks ‣ no knowledge of the implemented cryptographic primitive (if any) required • Three different attack realisations (varying attacker complexity) • Experiments show that it is possible to reduce the estimated distance to less than 3 m even though the devices were more than 50 m apart Aanjhan Ranganathan On the Security of Carrier Phase-based Ranging 7

Contributions • Investigate the vulnerability of carrier phase-based ranging system to distance modification attacks ‣ focus on distance reduction attacks ‣ no knowledge of the implemented cryptographic primitive (if any) required • Three different attack realisations (varying attacker complexity) • Experiments show that it is possible to reduce the estimated distance to less than 3 m even though the devices were more than 50 m apart 50 m Aanjhan Ranganathan On the Security of Carrier Phase-based Ranging 7

Contributions • Investigate the vulnerability of carrier phase-based ranging system to distance modification attacks ‣ focus on distance reduction attacks ‣ no knowledge of the implemented cryptographic primitive (if any) required • Three different attack realisations (varying attacker complexity) • Experiments show that it is possible to reduce the estimated distance to less than 3 m even though the devices were more than 50 m apart < 3 m 50 m Aanjhan Ranganathan On the Security of Carrier Phase-based Ranging 7

Phase-based Ranging θ Δ d θ Δ 7 Aanjhan Ranganathan On the Security of Carrier Phase-based Ranging 8

Phase-based Ranging θ Δ d θ 2 · f · ( θ c d = 2 π + n ) Δ θ 7 Aanjhan Ranganathan On the Security of Carrier Phase-based Ranging 8

Phase-based Ranging θ Δ d θ 2 · f · ( θ c d = 2 π + n ) Δ θ 7 ambiguity! Aanjhan Ranganathan On the Security of Carrier Phase-based Ranging 8

Phase-based Ranging f 1 θ θ 1 d = c 4 π · θ 2 − θ 1 Δ f 2 − f 1 d f 2 θ 2 · f · ( θ c d = 2 π + n ) Δ θ θ 2 7 ambiguity! Aanjhan Ranganathan On the Security of Carrier Phase-based Ranging 8

Distance Decreasing Relay Attacks Aanjhan Ranganathan On the Security of Carrier Phase-based Ranging 9

Distance Decreasing Relay Attacks System Assumption • Two entities, verifier (e.g., car) and a prover (e.g., key) estimate distance using multicarrier phase ranging technology • Verifier and prover implement some form of cryptographic authentication Aanjhan Ranganathan On the Security of Carrier Phase-based Ranging 9

Distance Decreasing Relay Attacks System Assumption • Two entities, verifier (e.g., car) and a prover (e.g., key) estimate distance using multicarrier phase ranging technology • Verifier and prover implement some form of cryptographic authentication Attacker Model • Verifier and prover are trusted and assumed to be honest • External attacker tries to reduce the estimated distance between a honest prover and verifier Aanjhan Ranganathan On the Security of Carrier Phase-based Ranging 9

Phase slope Rollover Attack d = c 4 π · θ 2 − θ 1 Distance f 1 f 2 − f 1 θ 1 f 2 θ 2 Aanjhan Ranganathan On the Security of Carrier Phase-based Ranging 10

Phase slope Rollover Attack d = c 4 π · θ 2 − θ 1 Distance f 1 f 2 − f 1 θ 1 4 π · ∆ θ max c Maximum d max = ∆ f measurable distance f 2 θ 2 Aanjhan Ranganathan On the Security of Carrier Phase-based Ranging 10

Phase slope Rollover Attack d = c 4 π · θ 2 − θ 1 Distance f 1 f 2 − f 1 θ 1 0 to 2 π 4 π · ∆ θ max c Maximum d max = ∆ f measurable distance f 2 θ 2 Aanjhan Ranganathan On the Security of Carrier Phase-based Ranging 10

Phase slope Rollover Attack d = c 4 π · θ 2 − θ 1 Distance f 1 f 2 − f 1 θ 1 0 to 2 π 4 π · ∆ θ max c Maximum d max = ∆ f measurable distance d max = c 1 f 2 2 · ∆ f θ 2 Aanjhan Ranganathan On the Security of Carrier Phase-based Ranging 10

Phase slope Rollover Attack d = c 4 π · θ 2 − θ 1 Distance f 1 f 2 − f 1 θ 1 0 to 2 π 4 π · ∆ θ max c Maximum d max = ∆ f measurable distance d max = c 1 f 2 2 · ∆ f ∆ f = 2 MHz , then d max = 75 m after which distance e.g., rollsover back to 0 θ 2 Aanjhan Ranganathan On the Security of Carrier Phase-based Ranging 10

Phase slope Rollover Attack d = c 4 π · θ 2 − θ 1 Distance f 1 f 2 − f 1 θ 1 0 to 2 π 4 π · ∆ θ max c Maximum d max = ∆ f measurable distance d max = c 1 f 2 2 · ∆ f ∆ f = 2 MHz , then d max = 75 m after which distance e.g., rollsover back to 0 θ 2 Attacker leverages this maximum measurable distance property to reduce the estimated distance Aanjhan Ranganathan On the Security of Carrier Phase-based Ranging 10

Phase slope Rollover Attack V P θ Δ t θ Δ t t Aanjhan Ranganathan On the Security of Carrier Phase-based Ranging 11

Phase slope Rollover Attack 80 V P Measured Distance [m] θ 60 Δ t 40 θ 20 Δ t 0 t 0 0.2 0.4 0.6 0.8 Delay [ 7 s] ∆ f = 2 MHz, then d max = 75 m Aanjhan Ranganathan On the Security of Carrier Phase-based Ranging 11

Phase slope Rollover Attack 80 V P Measured Distance [m] θ 60 Δ t 40 θ 20 500 ns Δ t 0 t 0 0.2 0.4 0.6 0.8 Delay [ 7 s] ∆ f = 2 MHz, then d max = 75 m Aanjhan Ranganathan On the Security of Carrier Phase-based Ranging 11