MRuby and Language Security with Daniel Bovensiepen

Shopify is a company that helps customers build custom online storefronts. Shopify has built upon the same Ruby on Rails application since the founding of their business 12 years ago starting with Rails 0.5 and moving all the way to Rails 5.  

MRuby is a lightweight implementation of the Ruby language. Shopify made the decision to use mruby to allow customers to create custom scripts that are run every time a customer adds items to their cart. However, since mruby was a language implementation that was not widely used, Shopify opted to post a Bug Bounty to the HackerOne bug bounty platform to find security vulnerabilities in their use of mruby. What followed was a payout of over $500,000 as report after report flooded in of security vulnerabilities inside mruby itself. There was so many reports that Shopify made the decision to sandbox the mruby execution into separate processes and decreased the bounty awards by 90%.

In this episode, Jeremy Jung interviews Daniel Bovensiepen (BOH-ven-see-pen) about mruby and the Shopify bug bounty.

Show Notes


The $500,000 release:

HackerOne bounty page:

American Fuzzy Lop:


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