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PREDICTING ZERO-DAY SOFTWARE VULNERABILITIES THROUGH DATA MINING

Su ZhangDepartment of Computing and Information ScienceKansas State University

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OUTLINE Motivation. Related work. Proposed approach. Possible techniques. Plan.

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OUTLINE Motivation. Related work. Proposed approach. Possible techniques. Plan.

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THE TREND OF VULNERABILITY NUMBERS

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ZERO-DAY VULNERABILITY

What is zero-day vulnerability? It is a vulnerability which is found by underground hackers

before being made public.

Increasing threat from zero-day vulnerabilities. Many attacks are attributed to zero-day vulnerabilities. E.g. in 2010 Microsoft confirmed a vulnerability in Internet

Explorer, which affected some versions that were released in 2001.

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OUR GOAL Risk awareness. The possibility of zero-day

vulnerability must be considered for comprehensive risk assessment for enterprise networks.

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ENTERPRISE RISK ASSESSMENT FRAMEWORK

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ENTERPRISE RISK ASSESSMENT FRAMEWORK

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ENTERPRISE RISK ASSESSMENT FRAMEWORK

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ENTERPRISE RISK ASSESSMENT FRAMEWORK

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ENTERPRISE RISK ASSESSMENT FRAMEWORK

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PROBLEMPredict the information of zero – day vulnerabilities from software configurations.

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OUTLINE Motivation. Related work. Proposed approach. Possible techniques. Plan.

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RELATED WORK

O. H. Alhazmi and Y. K. Malaiya, 2005.

Andy Ozment, 2007.

Kyle Ingols, et al, 2009.

Miles A. McQueen, et al, 2009.

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OUTLINE Motivation. Related work Proposed approach. Possible techniques. Plan.

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PROPOSED APPROACH Predict the likelihood of zero-day

vulnerabilities for specific software applications.

NVD Available since 2002. Rich data source including the preconditions and

consequences of vulnerabilities. It could be used to build our model and validate our work.

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SYSTEM ARCHITECTURE

IE WinXP FireFox …

Target Machine

Scanner (e.g. Nessus or OVAL)

Our Prediction Model

Output(MTTNV&CVSS Metrics)

CPE (common platform enumeration)

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PREDICTION MODEL

Predictive data: CPE (common platform enumeration) Indicate software configuration on a host.

Predicted data: MTTNV (Mean Time to Next

Vulnerability) & CVSS Metrics MTTNV indicates the probability of zero-day

vulnerabilities. CVSS metrics indicate the properties of the

predicted vulnerabilities.

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CPE (COMMON PLATFORM ENUMERATION) What is CPE?

CPE is a structured naming scheme for information technology systems, software, and packages.

Example (in primitive format) cpe:/a:acme:product:1.0:update2:pro:en-us Professional edition of the "Acme Product 1.0

Update 2 English".

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CPE LANGUAGE

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CVSS (COMMON VULNERABILITY SCORING SYSTEM ) An open framework for communicating the

characteristics and impacts of IT vulnerabilities.

Metric Vector access complexity (H, M, L) authentication ( R, NR) confidentiality (N, P, C) ...

CVSS Score: Calculated based on above vector. It indicates the severity of a vulnerability.

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CVSS USED IN RISK ASSESSMENT We use CVSS to derive a conditional

probability. How likely a vulnerability could be successfully exploited, given all preconditions fulfilled.

By combining the conditional probability with attack graph one can calculate the cumulative probability, we could obtain a overall estimated likelihood of the given machine being compromised.

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OUTLINE Motivation. Related work. Proposed approach. Possible techniques. Plan.

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POSSIBLE TECHNIQUES Linear Regression ( input are continuous

variables).

Statistical classification (input are discrete variables).

Maximum likelihood and least squares (Determining the parameters of our model).

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VALIDATION METHODOLOGY

Earlier years of NVD: Building our model.

Later years of NVD: Validate our model.

Criteria: Closer to the factual value than without considering zero-day vulnerabilities.

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OUTLINE Motivation. Related work. Proposed approach. Possible techniques. Plan.

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PLAN Next phase: Study data-mining tools (e.g.

Support Vector Machine) . Then build up our prediction model. Validate the model on NVD.

Final phase: If the previous phase provides a good model, we

will incorporate the generated result into MulVAL. Otherwise, we are going to investigate the

problem.

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REFERENCES [1]Andrew Buttner et al, ”Common Platform Enumeration (CPE) –

Specification,” 2008. [2]NVD, http://nvd.nist.gov/home.cfm. [3]O. H. Alhazmi et al, “Modeling the Vulnerability Discovery Process,”

2005. [4]Omar H. Alhazmi et al, “Prediction Capabilities of Vulnerability

Discovery Models,” 2006. [5]Andy Ozment, “Improving Vulnerability Discovery Models,” 2007. [6]R. Gopalakrishna and E. H. Spafford, “A trend analysis of

vulnerabilities,” 2005. [7]Christopher M. Bishop, “Pattern Recognition andMachine Learning,”

2006. [8]Xinming Ou et al, “MulVAL: A logic-based network security analyzer,”

2005. [9] Kyle Ingols et al, “Modeling Modern Network Attacks and

Countermeasures Using Attack Graphs” 2009. [10] Miles A. McQueen et al, “Empirical Estimates and Observations of

0Day Vulnerabilities,” 2009. [11] Alex J. Smola et al, “A Tutorial on Support Vector Regression,” 1998.

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THANK YOU!

Questions & Answers