Published about 5 years ago
Category: Attribute Restriction
Source: NIST NVD
Severity: Critical

Vulnerability in rails

There is a possible remote code execution vulnerability in Action Pack. This vulnerability has been assigned the CVE identifier CVE-2016-2098.


Applications that pass unverified user input to the render method in a controller or a view may be vulnerable to a code injection.

Impacted code will look like this:

class TestController < ApplicationController
  def show
    render params[:id]

An attacker could use the request parameters to coerce the above example to execute arbitrary ruby code.

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 render method. Instead, verify that data before passing it to the render method.

For example, change this:

def index
  render params[:id]

To this:

def index
  render verify_template(params[:id])

def verify_template(name)
  # add verification logic particular to your application here


To aid users who aren’t able to upgrade immediately we have provided a patch for it. It is in git-am format and consist of a single changeset.

  • 3-2-secure_inline_with_params.patch - Patch for 3.2 series
  • 4-1-secure_inline_with_params.patch - Patch for 4.1 series
  • 4-2-secure_inline_with_params.patch - Patch for 4.2 series


Thanks to both Tobias Kraze from makandra and joernchen of Phenoelit for reporting this!

CVSS Metrics
Access Vector Access Complexity Authentication Confidentiality Impact Integrity Impact Availability Impact
Network Network None Partial Partial Partial
Patched Versions

~> ~> 4.2.5 >= ~> 4.1.14 >=

Unaffected Versions

>= 5.0.0.beta1