CVE-2020-10663: Unsafe object creation in json RubyGem
Summary
CVE-2020-10663: Unsafe object creation in json RubyGem. Affects json versions < 2.3.0. Fixed in 2.3.0. How to fix ↓
Also tracked for
- ruby · Alpine:v3.10
The same CVE-2020-10663 is tracked separately for each ecosystem and vendor. Its fix information is the same; the package and affected versions differ.
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Background
The JSON gem is a Ruby library that provides JSON parsing and generation capabilities. It is widely used in Ruby applications for handling JSON data. The vulnerability affects versions 2.2.0 and below of the JSON gem, which are used in Ruby versions 2.4 through 2.4.9, 2.5 through 2.5.7, and 2.6 through 2.6.5. The vulnerability allows for unsafe object creation during JSON parsing, potentially leading to malicious object creation within the interpreter. This vulnerability is similar to CVE-2013-0269/GHSA-x457-cw4h-hq5f but does not rely on poor garbage-collection behavior within Ruby. The impact of this vulnerability depends on the specific application using the JSON gem.
Vulnerability Detail
The JSON gem through 2.2.0 for Ruby has an Unsafe Object Creation Vulnerability. When using JSON parsing methods, a malicious object can be created within the interpreter, which can have adverse effects depending on the application. This vulnerability does not rely on poor garbage-collection behavior within Ruby, making it distinct from a similar vulnerability in the past. The vulnerability has a CVSS score of 7.5.
How To Fix
Latest published version: 3.1.0 as of 23 Oct 2026
gem install json -v 3.1.0Upgrading to it may include breaking changes; the version below is the minimum fixed release for this vulnerability.
If you need the minimum change
2.3.0
This is the first release that contains the fix.
gem install json -v 2.3.0Tip — Not sure which version your app runs? Vulert can match this fix to it. Scan free →
Workaround
There is no known workaround for this vulnerability. It is necessary to upgrade the JSON gem to a fixed version.
Conclusion
The JSON gem through 2.2.0 for Ruby is vulnerable to an Unsafe Object Creation issue. It is recommended to upgrade the gem to version 2.3.0 or above to mitigate the vulnerability. Thorough testing should be performed after the upgrade to ensure compatibility and verify the resolution of the vulnerability. If you need further assistance or support in addressing this vulnerability, please contact DevNack.com.
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FAQ
The impact of this vulnerability depends on the specific application using the JSON gem. It could potentially allow for the creation of malicious objects within the interpreter, leading to various adverse effects.
You can use the Vulert Playground (https://vulert.com/scanner) to check if your application is affected by this vulnerability. Simply upload your manifest file (e.g., package-lock.json) and the tool will provide real-time alerts for open-source vulnerabilities.
Yes, the recommended fix is to upgrade the JSON gem to version 2.3.0 or above. This can be done by updating the gem version in the application's Gemfile and running the bundle update command.
Yes, this vulnerability affects Ruby versions 2.4 through 2.4.9, 2.5 through 2.5.7, and 2.6 through 2.6.5. It is important to upgrade the JSON gem in these versions to address the vulnerability.
Yes, the CVSS score for this vulnerability is 7.5.
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