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Ruby on Rails JSON Processor YAML Deserialization Code Execution

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Ruby on Rails JSON Processor YAML Deserialization Code Execution



This module exploits a remote code execution vulnerability in the JSON request processor of the Ruby on Rails application framework. This vulnerability allows an attacker to instantiate a remote object, which in turn can be used to execute any ruby code remotely in the context of the application. This vulnerability is very similar to CVE-2013-0156. This module has been tested successfully on RoR 3.0.9, 3.0.19, and 2.3.15. The technique used by this module requires the target to be running a fairly recent version of Ruby 1.9 (since 2011 or so). Applications using Ruby 1.8 may still be exploitable using the init_with() method, but this has not been demonstrated.


  • jjarmoc
  • egypt <egypt@metasploit.com>
  • lian






Module Options

To display the available options, load the module within the Metasploit console and run the commands 'show options' or 'show advanced':

msf > use exploit/multi/http/rails_json_yaml_code_exec
msf exploit(rails_json_yaml_code_exec) > show targets
msf exploit(rails_json_yaml_code_exec) > set TARGET < target-id >
msf exploit(rails_json_yaml_code_exec) > show options
    ...show and set options...
msf exploit(rails_json_yaml_code_exec) > exploit

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