09-05, 14:00–14:30 (Europe/Amsterdam), Second track
This talk will present details of the TETRA:BURST vulnerabilities - the result of the first public in-depth security analysis of TETRA (Terrestrial Trunked Radio). This European standard for trunked radio is used globally by government agencies, police, military, and critical infrastructure, for applications ranging from voice communications to SCADA telecontrol of energy distribution, oil rigs and train safety systems.
Authentication and encryption within TETRA are handled by proprietary cryptographic cipher-suites, which had previously remained secret for over two decades through the use of restrictive NDAs. Last year, we presented the result of a two-year research project, and disclosed both open-source implementations of the secret primitives as well as a first public security assessment of the technology. Several critical vulnerabilities were identified, including a deliberate backdoor.
This talk is an overview of the most important of the five uncovered issues, collectively dubbed TETRA:BURST.
First, we uncover the presence of a deliberate backdoor in the TEA1 cipher, which is used in critical infrastructure. This backdoor reduces the effective key strength from 80 to 32 bits, rendering it vulnerable to an exhaustive search attack. The demonstrated attack is fully passive, and runs in under a minute.
Second, we present a keystream recovery attack which works regardless of the cipher employed, affecting all encrypted TETRA networks.
Furthermore, we discuss a de-anonymization attack with counter-intelligence implications and a flaw in the authentication protocol.
Additionally, we provide the attendee with background information on TETRA's role in critical infrastructure as a SCADA telecontrol link, and how the TEA1 backdoor proliferated throughout Europe, exposing our critical infrastructure as well as several European military and police users to very severe risks.
See https://midnightblue.nl/tetraburst for more details.
Wouter Bokslag is a co-founding partner and security researcher at Midnight Blue. He is known for the reverse-engineering and cryptanalysis of several proprietary in-vehicle immobilizer authentication ciphers used by major automotive manufacturers as well as co-developing the world's fastest public attack against the Hitag2 cipher. He holds a Master's Degree in Computer Science & Engineering from Eindhoven University of Technology (TU/e) and designed and assisted in teaching hands-on offensive security classes for graduate students at the Dutch Kerckhoffs Institute for several years.
He co-authored the TETRA:BURST research and currently provides security consultancy services for clients ranging from government agencies and critical infrastructure to IT and OT companies across industry verticals.