Summary

Dynamic Method Invocation disabled by default

Who should read this

All Struts 2 developers and users

Impact of vulnerability

Dynamic method executions

Maximum security rating

Important

Recommendation

Developers should immediately upgrade to Struts 2.3.15.2

Affected Software

Struts 2.0.0 - Struts 2.3.15.1

Reporter

shine@wooyun.org, HelloWorld security team

CVE Identifier

CVE-2013-4316

Problem

Dynamic Method Invocation is a mechanism known to impose possible security vulnerabilities, but until now it was enabled by default with warning that users should switch it off if possible.

Solution

In Struts 2.3.15.2 the Dynamic Method Invocation is to false by default. Another option is to set struts.enable.DynamicMethodInvocation to false in struts.xml

<constant name="struts.enable.DynamicMethodInvocation" value="false"/>

Disabling Dynamic Method Invocation can break your application if it uses DMI heavily. Nevertheless, please consider to refactor your application to avoid DMI.

It is strongly recommended to upgrade to Struts 2.3.15.2, which contains the corrected Struts2-Core library.