CVE-2021-4188: Mruby

High severity, CVSS 7.5. EPSS: 0.9% chance of exploitation in the next 30 days.

mruby is vulnerable to NULL Pointer Dereference

Affected products

• Mruby Mruby: up to and including 3.0.0

Published 2021-12-30. Last modified 2026-06-17.