Firefox 5.0 - 15.0.1 __exposedProps__ XCS Code Execution
Description
On versions of Firefox from 5.0 to 15.0.1, the InstallTrigger global, when given invalid input, would throw an exception that did not have an __exposedProps__ property set. By re-setting this property on the exception object's prototype, the chrome-based defineProperty method is made available. With the defineProperty method, functions belonging to window and document can be overridden with a function that gets called from chrome-privileged context. From here, another vulnerability in the crypto.generateCRMFRequest function is used to "peek" into the context's private scope. Since the window does not have a chrome:// URL, the insecure parts of Components.classes are not available, so instead the AddonManager API is invoked to silently install a malicious plugin.
Author(s)
- Mariusz Mlynski
- moz_bug_r_a4
- joev <joev@metasploit.com>
Platform
Java,Linux,OSX,Solaris,Windows
Development
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/browser/firefox_proto_crmfrequest
msf exploit(firefox_proto_crmfrequest) > show targets
...targets...
msf exploit(firefox_proto_crmfrequest) > set TARGET < target-id >
msf exploit(firefox_proto_crmfrequest) > show options
...show and set options...
msf exploit(firefox_proto_crmfrequest) > exploit
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