Ruby 4.0 Universal RCE Deserialization Gadget Chain
Summary
Describes a universal gadget chain allowing command execution via Marshal.load on Ruby 4.0.6 and older versions. It traces the evolution of Ruby deserialization attacks, explains the gadgets and the payload assembly, and shows how RubyGems and standard library components can be chained to achieve remote code execution. The article also discusses mitigations and the broader implications for Ruby deployments.