A vulnerability introduced by manipulating parameters prefixed with "action:"/"redirect:"/"redirectAction:" allows remote command execution
Who should read this
All Struts 2 developers and users
Impact of vulnerability
Remote command execution
Maximum security rating
Developers should immediately upgrade to Struts 220.127.116.11
Struts 2.0.0 - Struts 2.3.15
Takeshi Terada of Mitsui Bussan Secure Directions, Inc.
The Struts 2 DefaultActionMapper supports a method for short-circuit navigation state changes by prefixing parameters with "action:" or "redirect:", followed by a desired navigational target expression. This mechanism was intended to help with attaching navigational information to buttons within forms.
In Struts 2 before 18.104.22.168 the information following "action:", "redirect:" or "redirectAction:" is not properly sanitized. Since said information will be evaluated as OGNL expression against the value stack, this introduces the possibility to inject server side code.
Proof of concept
In the Struts Blank App, open following URLs.
- Simple Expression - the parameter names are evaluated as OGNL.
- Command Execution
DefaultActionMapper was changed to sanitize "action:"-prefixed information properly. The features involved with "redirect:"/"redirectAction:"-prefixed parameters were completely dropped - see also S2-017.
It is strongly recommended to upgrade to Struts 22.214.171.124, which contains the corrected Struts2-Core library.