Possible Information Leak Vulnerability in Action View.
There is a possible directory traversal and information leak vulnerability in Action View. This was meant to be fixed on CVE-2016-0752. However the 3.2 patch was not covering all the scenarios. This vulnerability has been assigned the CVE identifier CVE-2016-2097.
Versions Affected: 3.2.x, 4.0.x, 4.1.x Not affected: 4.2+ Fixed Versions: 184.108.40.206, 220.127.116.11
Applications that pass unverified user input to the
render method in a
controller may be vulnerable to an information leak vulnerability.
Impacted code will look something like this:
Carefully crafted requests can cause the above code to render files from unexpected places like outside the application's view directory, and can possibly escalate this to a remote code execution attack.
All users running an affected release should either upgrade or use one of the workarounds immediately.
The FIXED releases are available at the normal locations.
A workaround to this issue is to not pass arbitrary user input to the
method. Instead, verify that data before passing it to the
For example, change this:
```ruby def index render verify_template(params[:id]) end
private def verify_template(name) # add verification logic particular to your application here end ```
Thanks to both Jyoti Singh and Tobias Kraze from makandra for reporting this and working with us in the patch!