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Security and Privacy in Cloud Computing. Ragib Hasan Johns Hopkins University en.600.412 Spring 2011. Lecture 10 04/ 18/ 2011. Malware and Clouds. Goal : To explore how clouds can be used in malware detection, and how malware can use clouds. Review Assignment #9 :
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Security and Privacy in Cloud Computing Ragib HasanJohns Hopkins Universityen.600.412 Spring 2011 Lecture 10 04/18/2011
Malware and Clouds • Goal: To explore how clouds can be used in malware detection, and how malware can use clouds. • Review Assignment #9: • CloudAV: N-Version Antivirus in the Network Cloud, USENIX Security, 2008. en.600.412 Spring 2011 Lecture 10 | JHU | Ragib Hasan
Cloud-AV: Putting the Antivirus on Clouds Main premise: • Executable analysis currently provided by host-based antivirus software can be more efficiently and effectively provided as an in-cloud network service. • Or • Anti-Virus-as-a-service en.600.412 Spring 2011 Lecture 10 | JHU | Ragib Hasan
Problems with host-based Anti-Virus • Vulnerability window: • There is a significant vulnerability window between when a threat first appears and when antivirus vendors generate a signature. • Undetected malware: • a substantial percentage of malware is never detected by antivirus software • Vulnerable Anti-Virus: • Malware is actually using vulnerabilities in antivirus software itself as a means to infect systems en.600.412 Spring 2011 Lecture 10 | JHU | Ragib Hasan
Solution Approach • Antivirus as a network service: • Run the Anti-virus on a cloud, while running a lightweight agent on user machines • N-version protection • Run multiple versions/vendor Anti-Virus/scanners on the cloud to ensure better detection en.600.412 Spring 2011 Lecture 10 | JHU | Ragib Hasan
N-version programming Idea: Generate multiple functionally equivalent programs independently (by different teams) from the same initial specifications • Goal: Reduce possibility of bugs N version protection: • Run multiple scanners in parallel, to increase detection rate en.600.412 Spring 2011 Lecture 10 | JHU | Ragib Hasan
Advantages of cloud based anti-Virus Better detection of malicious software Enhanced forensics capabilities Retrospective detection Improved deployability and management No vendor lock-in … service is vendor agnostic en.600.412 Spring 2011 Lecture 10 | JHU | Ragib Hasan
System Architecture 3 major components: a lightweight host agent run on end hosts a network service that receives files from hosts and identifies malicious or unwanted content; and an archival and forensics service that stores information about analyzed files and provides a management interface for operators. en.600.412 Spring 2011 Lecture 10 | JHU | Ragib Hasan
Host agent • A lightweight process running on host • Can be Implemented on Windows, Mac, Linux clients • Tasks: • Capture accesses to executable files, • hashe files to extract unique ID, • check ID against local black/white lists, • send unknown executable files to network cloud service en.600.412 Spring 2011 Lecture 10 | JHU | Ragib Hasan
Network service • Consists of multiple Anti-Virus, scanners, and behavioral analysis tools • Behavioral analysis tools attempt to detect anomaly by analyzing app behavior in a sandbox • Combines scan results from multiple tools and sends report to host agent en.600.412 Spring 2011 Lecture 10 | JHU | Ragib Hasan
Forensic storage service Stores information about scan logs, hosts Can assist in forensic analysis and retroactive scans en.600.412 Spring 2011 Lecture 10 | JHU | Ragib Hasan
Challenges • Network latency: • unlike existing antivirus software, files must transported into the network for analysis; • Analysis scheme: • an efficient analysis system must be constructed to handle the analysis of files from many different hosts using many different detection engines in parallel; and • Comparison with local scanners: • the performance of the system must be similar or better than existing detection systems such as antivirus software. en.600.412 Spring 2011 Lecture 10 | JHU | Ragib Hasan
Evaluations: Performance of multiple Anti-Virus engines en.600.412 Spring 2011 Lecture 10 | JHU | Ragib Hasan
Disadvantages Disconnected operation: • Host agent can’t detect new malicious files without network connectivity Lack of context: • Scanners do not have access to large local context Handling new malware: • Difficult to detect non executable malware (e.g., malicious word documents) en.600.412 Spring 2011 Lecture 10 | JHU | Ragib Hasan
Discussion What other services can be run on a cloud? en.600.412 Spring 2011 Lecture 10 | JHU | Ragib Hasan
Using Clouds for Malware • Clouds can be used by malicious parties • Misuse can include: • Cloud based botnets • Cloud based spammers • Cloud based cracking services • WPACracker.com – Claims to break WPA passwords for $17 in under 20 minutes, using a cloud en.600.412 Spring 2011 Lecture 10 | JHU | Ragib Hasan
Discussion Is it realistic / feasible for a spammer to use a cloud? en.600.412 Spring 2011 Lecture 10 | JHU | Ragib Hasan