In Struts prior to 2.5.22, stack-accessible values (e.g. Action properties) of type java.io.File and java.nio.File as well as other classes from these standard library packages are not properly protected by the framework to deny access to potentially harmful underlying properties.
When a file upload is performed to an Action that exposes the file with a getter, an attacker may manipulate the request such that the working copy of the uploaded file is set to read-only. As a result, subsequent actions on the file will fail with an error. It might also be possible to set the Servlet container's temp directory to read only, such that subsequent upload actions will fail. |