Black-box testing of web applications with client-side code evaluation

• US 9,032,528 B2
• Filed: 06/28/2011
• Issued: 05/12/2015
• Est. Priority Date: 06/28/2011
• Status: Active Grant

• Current Assignee: Finjan Blue, Inc. (FIG LLC (d/b/a Fortress Investment Group LLC))
• Original Assignee: International Business Machines Corporation
• Inventors: Haviv, Yinnon A., Kalman, Daniel, Pikus, Dmitri, Tripp, Omer, Weisman, Omri
• Primary Examiner(s): McNally, Michael S
• Application Number:
  US13/170,839
• Publication Number:
  US 20130007885A1
• Time in Patent Office: 1,414 Days
• Field of Search: 726/22, 726/25
• US Class Current: 726/25
• CPC Class Codes: G06F 21/577 Assessing vulnerabilities and evaluating computer system security
• CPC Class Codes: H04L 63/1433 Vulnerability analysis
• CPC Class Codes: H04L 63/1441 Countermeasures against malicious traffic countermeasures against attacks on cryptographic mechanisms H04L9/002

Abstract

Detecting security vulnerabilities in web applications by interacting with a web application at a computer server during its execution at the computer server, identifying client-side instructions provided by the web application responsive to an interaction with the web application, where the client-side instructions are configured to be implemented by a client computer that receives the client-side instructions from the computer server, evaluating the identified client-side instructions, and identifying a security vulnerability associated with the client-side instructions.

Claims

1. A system for detecting security vulnerabilities in web applications, the system comprising:

at least one hardware processor, wherein

the at least one hardware processor includes a block-box tester, and a client-side evaluator,

the black-box tester is configured to

interact with a web application at a computer server during its execution at the computer server, and

identify client-side instructions provided by the web application responsive to an interaction with the web application,

the client-side instructions are configured to be implemented by a client computer that receives the client-side instructions from the computer server; and

the client-side evaluator is configured to

evaluate the client-side instructions identified by the black-box tester, and

identify a security vulnerability associated with the client-side instructions.

2. The system of claim 1 where

the black-box tester is configured to identify a security vulnerability associated with the web application.

3. The system of claim 1 where

the client-side evaluator is configured to perform static analysis of the client-side instructions identified by the black-box tester to identify the security vulnerability associated with the client-side instructions.

4. The system of claim 1 where

the client-side evaluator is configured to perform dynamic taint analysis on the client-side instructions to track taint propagation within the client-side instructions, thereby identifying the security vulnerability associated with the client-side instructions.

5. The system of claim 4 where

the client-side evaluator is configured to modify the client-side instructions identified by the black-box tester to store information indicating whether variables within the client-side instructions point to tainted objects, and where

the client-side evaluator is configured to perform dynamic taint analysis on the modified client-side instructions to track taint propagation within the modified client-side instructions, thereby identifying the security vulnerability associated with the client-side instructions.

6. The system of claim 4 where

the client-side evaluator is configured to use a predefined security specification to determine which objects within the client-side instructions are tainted and how taint propagates from variable to variable within the client-side instructions.

7. The system of claim 4 and further comprising

an interpreter configured to track any variable within the client-side instructions that directly points to a tainted object within the client-side instructions, where

the client-side evaluator is configured to perform dynamic taint analysis on the client-side instructions by calling the interpreter to track taint propagation within the client-side instructions, thereby identifying the security vulnerability associated with the client-side instructions.

8. The system of claim 7 where

the interpreter is configured to track any variable that ultimately depends from any variable within the client-side instructions that directly points to a tainted object within the client-side instructions.

9. The system of claim 7 where

the interpreter is configured to use a predefined security specification to determine which objects within the client-side instructions are tainted and how taint propagates from variable to variable within the client-side instructions.

10. The system of claim 4 and further comprising

a symbolic analyzer configured to perform symbolic analysis of the client-side instructions to determine at least one value for at least one variable within the client-side instructions that would result in a control flow target being reached within the client-side instructions during execution of the client-side instructions, where

the client-side evaluator is configured to use any value determined by the symbolic analyzer when performing the dynamic taint analysis on the client-side instructions to cause the target control flow.

11. A computer program product for detecting security vulnerabilities in web applications, the computer program product comprising:

a computer-readable storage medium; and

computer-readable program code embodied in the computer-readable storage medium, where the computer-readable program code is configured to

interact with a web application at a computer server during its execution at the computer server,

identify client-side instructions provided by the web application responsive to an interaction with the web application, where

the client-side instructions are configured to be implemented by a client computer that receives the client-side instructions from the computer server,

evaluate the client-side instructions, and

identify a security vulnerability associated with the client-side instructions, wherein

the computer-readable storage medium is not a transitory, propagating signal per se.

12. The computer program product of claim 11 where

the computer-readable program code is configured to identify a security vulnerability associated with the web application.

13. The computer program product of claim 11 where

the computer-readable program code is configured to perform static analysis of the client-side instructions to identify the security vulnerability associated with the client-side instructions.

14. The computer program product of claim 11 where

the computer-readable program code is configured to perform dynamic taint analysis on the client-side instructions to track taint propagation within the client-side instructions, thereby identifying the security vulnerability associated with the client-side instructions.

15. The computer program product of claim 14 where

the computer-readable program code is configured to

modify the client-side instructions to store information indicating whether variables within the client-side instructions point to tainted objects, and

perform dynamic taint analysis on the modified client-side instructions to track taint propagation within the modified client-side instructions, thereby identifying the security vulnerability associated with the client-side instructions.