Addressing Future Challenges in the Development of Safe and Secure Software Components The MathWorks, Inc. 1

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1 Addressing Future Challenges in the Development of Safe and Secure Software Components 2016 The MathWorks, Inc. 1

2 Cybersecurity Emerging Topic in the Auto Industry Vehicle-to-Infrastructure Wifi Hotspot Wireless Key Remote Start Internet Connection Tire Pressure Monitor Vehicle-to-Vehicle ecall Bluetooth Connection 2

3 Growing security concerns rise in number and complexity In 2013, 2164 separate incidents, over 822 million records were exposed, nearly doubling the previous highest year on record (2011). Hacking accounted for almost 60% of incidents.. US has by far the biggest share of pain with 48.7% of the total.. Continued to increase in 2014 and 2015 Researchers demonstrated a proof-of-concept attack where they managed to take control of a vehicle remotely Sources:

4 Conflicting Safety & Security Goals When the full locking system is employed, the interior operations for unlocking the door locking mechanism are disengaged, which makes the locking system an effective anti-theft measure. However, if the doors cannot be opened by an occupant from inside the vehicle, they may be trapped inside. Resulted in recall of more than 6000 cars Source: 4

5 Communication between Cybersecurity and Safety Process Source: SAE 3061 Cyber Security Framework 5

6 Cybersecurity Industry Activities & Standards SAE Vehicle Cybersecurity Systems Engineering Committee SAE J Cybersecurity Guidebook for Cyber-Physical Vehicle Systems SAE J Requirements for Hardware-Protected Security for Ground Vehicle Applications (WIP) SAE Cybersecurity Assurance Testing Task Force (TEVEES18A1) Coding standards & practices that we observe at automotive customers - CERT C - ISO/IEC TS C Secure Coding Rules - CWE Common Weakness Enumeration - MISRA-C:2012 Amendment 1 6

7 Example Cybersecurity Lifecycle (SAE 3061) Concept Phase Requirements Phase Assets and Attack Potentials Threat and Risk Assessment Cybersecurity Goals Validate Security Assumptions Cybersecurity Case Design Phase Product Development Phase System-level Cybersecurity Concept Technical Cybersecurity Concept Implement Security Mechanism Test Security Mechanisms & Penetration Tests Item Integration & Testing Validation & Verification Phase Secure Implementation of Nominal Functions Source: SAE 3061 Cyber Security Framework 7

8 Threat Modeling & Attack Tree Analysis *Referring to SAE J3061 Appendix A.1 OVERVIEW OF THREAT ANALYSIS & RISK ASSESSMENT AND VULNERABILITY ANALYSIS METHODS: Vulnerability analysis can be performed at different levels; the system level, hardware level, and software level. Some analysis methods, such as attack trees, may be used across different levels. Identifying flaws as early as possible in the CPS design is 5 to 10 less expensive than finding them during the detailed design stages. Source: G. Fortney. Model based systems engineering using validated executable specifications as an enabler for cost and risk reduction. Proceedings of the 2014 Ground Vehicle Systems Engineering and Technology Symposium (GVSETS),

9 Model-Based Safety/Security Analysis Simulink Model of a function Maintain safe distance by braking Property proving (e.g., Simulink Design Verifier) Violated Counterexamples Satisfied 9

10 Model-Based Safety/Security Analysis Assets and Attack Potentials 10

11 Model-Based Safety/Security Analysis Simulink Model of a function Maintain safe distance by braking Threat models Threat and Risk Assessment Property proving (e.g., Simulink Design Verifier) Violated Counterexamples Satisfied 11

12 Model-Based Safety/Security Analysis Simulink Model of a function Maintain safe distance by braking Interruption attack Man-in-the-middle attack Overflow attack Downsampling attack Threat and Risk Assessment Property proving (e.g., Simulink Design Verifier) Violated Counterexamples Satisfied 12

13 Model-Based Safety/Security Analysis 13

14 Smart Fuzz Testing Identifying System Vulnerabilities Fuzzing is a technique whereby an application is fed malformed input data with the aim to detect anomalies in the processing of unexpected data entry System under Test Define Violation Criterion Smart fuzz test stimuli Leverage smart fuzz testing to identify vulnerabilities Define intended cybersecurity violation Automated test/attack case generation 14

15 Automation to handle design Trade-offs Check Modified Design Code generation C Code Improvement Suggestions 15

16 Coding Standards Overview Coding Standard C Standard Security Standard Safety Standard International Standard CWE None/all Yes No No N/A MISRA C:2004 C89 No Yes No No MISRA C:2012* C99 No Yes No No CERT C99 C99 Yes No No Yes CERT C11 C11 Yes Yes No Yes ISO/IEC TS C11 Yes No Yes Yes *) 04/2016: Additional security guidelines for MISRA-C:2012 Amendment 1 Whole Language Source: Table is based on the book: 16

17 CWE : Common Weakness Enumeration Not limited to the C programing language Not limited to potential issues caused by source code E.g.: CWE-5: J2EE Misconfiguration: Data Transmission Without Encryption Includes CERT C 18

18 SEI CERT C Coding Standard This coding standard consists of rules and recommendations, collectively referred to as guidelines. Rules are meant to provide normative requirements for code, whereas Actual: 98 Rules (depending on applicable categories) Recommendations are meant to provide guidance that, when followed, should improve the safety, reliability, and security of software systems. Actual: 178 Recommendations (depending on applicable categories) 19

19 L2 Example: Rule 05. Floating Point (FLP) 21

20 Mapping to MISRA C:

21 Potential Cert C issues * FLP30-C 2 Do not use floating-point variables as loop counters FLP34-C 41 Ensure that floating-point conversions are within range of the new type INT30-C 72 Ensure that unsigned integer operations do not wrap INT31-C 343 Ensure that integer conversions do not result in lost or misinterpreted data *) all user made; found in C code generated from 50 industry models 23

22 Potential Cert C issues * Reason: models have not been designed to comply with Cert C (issues are specifically relevant if taint data is involved) FLP30-C 2 Do not use floating-point variables as loop counters FLP34-C 41 Ensure that floating-point conversions are within range of the new type INT30-C 72 Ensure that unsigned integer operations do not wrap INT31-C 343 Ensure that integer conversions do not result in lost or misinterpreted data *) all user made; found in C code generated from 50 industry models 24

23 Automated analysis Defects related to Code elements from an unsecure source (e.g. parameters, globals, etc.) Example: Array access with tainted index /* Use Index to Return Buffer Value */ #define SIZE extern int tab[size100]; int taintedarrayindex(int num) { return tab[num]; } 25

24 Automated analysis: e.g. Static Taint Analysis detects issues Defects related to Code elements from an unsecure source Example: Array access with tainted index /* Use Index to Return Buffer Value */ #define SIZE extern int tab[size100]; int taintedarrayindex(int num) { return tab[num]; } 26

25 Automated analysis: e.g. Static Taint Analysis satisfies standards Defects related to Code elements from an unsecure source Example: Array access with tainted index /* Use Index to Return Buffer Value */ #define SIZE extern int tab[size100]; int taintedarrayindex(int num) { return tab[num]; } 27

26 Automated analysis: e.g. Static Taint Analysis on the fix... Defects related to Code elements from an unsecure source Example: Array access with tainted index /* Use Index to Return Buffer Value */ #define SIZE extern int tab[size100]; int taintedarrayindex(int num) { if (num >= 0 && num < SIZE100) { return tab[num]; } else { return -9999; } } 28

27 Automated analysis: e.g. Analysis with Formal Proof Defects related to Code elements from an unsecure source Example: Array access with tainted index /* Use Index to Return Buffer Value */ #define SIZE extern int tab[size100]; int taintedarrayindex(int num) { if (num >= 0 && num < SIZE100) { return tab[num]; } else { return -9999; } } 29

28 A static and semantic code analysis tool helps you to... Identify defects Enforce coding rules Produce and monitor quality metrics 30

29 Key Takeaways and call to action Adressing cyber-security uses processes, methods and tools known from functional safety domain, with different scope Static and semantic code analysis provides a quick start to identify security vulnerabilities and assess coding standard compliance Model-based design streamlines efforts for meeting existing and emerging safety & security standard compliance 31

30 Questions!?! Thank You! 32