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.
github.com/nov/json-jwt
github.com/nov/json-jwt/commit/593ea8bcaf2629048bad8c036191f2da0a2e713c
github.com/nov/json-jwt/commit/9c4d842a9465bd7960570ca326c3de79b4abc9d0
github.com/nov/json-jwt/issues/120
github.com/nov/json-jwt/issues/121
github.com/P3ngu1nW/CVE_Request/blob/main/novjson-jwt.md
github.com/rubysec/ruby-advisory-db/blob/master/gems/json-jwt/CVE-2023-51774.yml
nvd.nist.gov/vuln/detail/CVE-2023-51774