Describe CVE-2021-21305.
What is CVE-2021-21305?
CarrierWave is an open-source RubyGem which provides a simple and flexible way to upload files from Ruby applications. In CarrierWave before versions 1.3.2 and 2.1.1, there is a code injection vulnerability. The "#manipulate!" method inappropriately evals the content of mutation option(:read/:write), allowing attackers to craft a string that can be executed as a Ruby code. If an application developer supplies untrusted inputs to the option, it will lead to remote code execution(RCE). This is fixed in versions 1.3.2 and 2.1.1..