A CSRF forgery vulnerability exists in rails < 5.2.5, rails < 6.0.4 that makes it possible for an attacker to, given a global CSRF token such as the one present in the authenticity_token meta tag, forge a per-form CSRF token.
A denial of service vulnerability exists in Rails <6.0.3.2 that allowed an untrusted user to run any pending migrations on a Rails app running in production.
A deserialization of untrusted data vulnernerability exists in rails < 5.2.4.3, rails < 6.0.3.1 that can allow an attacker to unmarshal user-provided objects in MemCacheStore and RedisCacheStore potentially resulting in an RCE.
A client side enforcement of server side security vulnerability exists in rails < 5.2.4.2 and rails < 6.0.3.1 ActiveStorage's S3 adapter that allows the Content-Length of a direct file upload to be modified by an end user bypassing upload limits.
A deserialization of untrusted data vulnerability exists in rails < 5.2.4.3, rails < 6.0.3.1 which can allow an attacker to supply information can be inadvertently leaked fromStrong Parameters.