GHSA-c8v6-786g-vjx6 json-jwt allows bypass of identity checks via a sign/encryption confusion attack

• RubyGems json-jwt: >= 1.16.0, < 1.16.6 → fixed in 1.16.6 • RubyGems json-jwt: < 1.15.3.1 → fixed in 1.15.3.1

The json-jwt (aka JSON::JWT) gem 1.16.x before 1.16.6, 1.15.x before 1.15.3.1 for Ruby sometimes allows bypass of identity checks via a sign/encryption confusion attack. For example, JWE can sometimes be used to bypass JSON::JWT.decode.