Summary

Cross-Site Scripting Vulnerability in Debug Mode and in exposed JSP files

Who should read this

All Struts 2 developers and users

Impact of vulnerability

Affects of a cross-site scripting vulnerability when debug mode is switched on or JSPs are exposed in production environment.

Maximum security rating

Low

Recommendation

Turn off debug mode in production environment, apply tips from Security guideline to secure JSPs. An upgrade to Struts 2.3.20 is recommended.

Affected Software

Struts 2.0.0 - Struts Struts 2.3.16.3

Reporter

Takayoshi Isayama, Mitsui Bussan Secure Directions, Inc. (vulnerability with JSPs)

anonymous (vulnerability with devMode)

CVE Identifier

CVE-2015-5169

Problem

When the Struts2 debug mode is turned on, under certain conditions an arbitrary script may be executed in the 'Problem Report' screen. Also if JSP files are exposed to be accessed directly it's possible to execute an arbitrary script.

Solution

It is generally not advisable to have debug mode switched on outside of the development environment. Debug mode should always be turned off in production setup. Also never expose JSPs files directly and hide them inside WEB-INF folder or define dedicated security constraints to block access to raw JSP files. Please also read our Security guide - it contains useful informations how to secure your application.

Struts >= 2.3.20 is not vulnerable to this attack. We recommend upgrading to Struts 2.3.20 or higher.

Backward compatibility

No backward compatibility problems are expected.

Workaround

Upgrade to Struts 2.3.20