Advanced Systems Security: Putting It Together Systems

Transcription

1 Systems and Internet Infrastructure Security Network and Security Research Center Department of Computer Science and Engineering Pennsylvania State University, University Park PA Advanced Systems Security: Putting It Together Systems Trent Jaeger Systems and Internet Infrastructure Security (SIIS) Lab Computer Science and Engineering Department Pennsylvania State University Page 1

2 Problem Deploy Your Code To Process Your Data Start with important data and the code you trust to modify that data What could go wrong? Page 2

3 Problem: Malware 53% of computers contain malware Out of 21 million scanned (2010) What may happen when you run your program on a computer with malware? Malware running as you Malware running as root How do you avoid running a system with malware? Page 3

4 Problem: Phishing Social engineering attacks Trick user into exposing credentials Malicious web application mimics real one Users use as if this is a legitimate website Release credentials How do you ensure users avoid phishing attacks? Page 4

5 Problem: Malicious Insiders Run computation in a managed environment Using a certified host image However, an adversary may have access to the compute node s management interface Both malicious and accidental misconfiguration Can lead to the leakage of valuable data How do you avoid using a mismanaged node? Page 5

6 Security Technology Galore Hardware Trusted computing Virtualization OS Middleware (Web, JVM, Android, etc.) Application Network Page 6

7 Put It Together Can we use these technologies to prevent the attacks above? Trusted computing, Virtualization, OS, Middleware (Web, JVM, Android, etc.), Application, Network How do we put them together? Can we just install them and gain a secure system? What guides how we construct secure systems from these mechanisms? Page 7

8 How to Put Together? Define security goals Define trust model Define threat model Provide reference monitoring necessary Validate satisfaction of RM concept Write security policy that ensures goals, when enforced by your reference monitor Validate satisfaction of security goals, given trust and threats Page 8

9 Unicorn Page 9

10 Answers for Unicorn Define security goals Define trust model Define threat model Provide reference monitoring necessary Validate satisfaction of RM concept Write security policy that ensures goals, when enforced by your reference monitor Validate satisfaction of security goals, given trust and threats Page 10

11 Excalibur (Policy-Sealed Data) Page 11

12 Answers for Excalibur Define security goals Define trust model Define threat model Provide reference monitoring necessary Validate satisfaction of RM concept Write security policy that ensures goals, when enforced by your reference monitor Validate satisfaction of security goals, given trust and threats Page 12

13 Take Away Just having the technology is not enough Need expertise to put them together A lot of decisions need to be made Somewhat informally related to reference monitor concept, security models currently Reference monitors define flows among threats and valuable processing Use this to determine where concrete threats lie Still some manual work Page 13