Chrome For Android API Exposure

`CVE Number: CVE-2012-4907  
Title: Chrome for Android - Android APIs exposed to JavaScript  
Affected Software: Confirmed on Chrome for Android v18.0.1025123  
Credit: Takeshi Terada  
Issue Status: v18.0.1025308 was released which fixes this vulnerability  
  
Overview:  
By abusing Java objects exposed to JavaScript, malicious Web pages can execute  
arbitrary commands on Chrome for Android, if the accessibility setting of the  
device is enabled.  
  
Details:  
Chrome for Android (v18.0.1025123) is prone to remote command execution  
vulnerability. When a Chrome user visits a malicious Web page, the JavaScript  
in the page can execute arbitrary commands (Java methods) in the context of  
Chrome app.  
  
Only users who have enabled device's accessibility setting are affected.  
Accessibility setting is for those who have visual or physical limitations,  
and is disabled by default. It is enabled by some apps such as TalkBack,  
ClockBack and so on.  
  
The root cause of the issue is:  
  
1. Chrome automatically exposes some Java objects (e.g. "accessibility")  
to JavaScript if the device's accessibility setting is enabled.  
  
2. And JavaScript is allowed to gain access to Java's ClassLoader via  
Java objects exposed to JavaScript.  
  
Proof of Concept:  
At present I do not have plans to disclose PoC for this issue.  
  
Timeline:  
2012/07/08 Reported to Google security team.  
2012/09/12 Vender announced v18.0.1025308  
2013/01/07 Disclosure of this advisory  
  
Recommendation:  
Upgrade to the latest version.  
  
Reference:  
http://googlechromereleases.blogspot.jp/2012/09/chrome-for-android-update.html  
https://code.google.com/p/chromium/issues/detail?id=144813  
  
Note:  
The idea of this attack came from below Web page (Japanese).  
http://www.kanasansoft.com/weblab/2012/04/webview_addjavascriptinterface_of_android_is_dangerous.html  
`