Disable claim validation if no expected values given

Author: anakinj

CHANGELOG.md

@@ -10,6 +10,7 @@
 
 **Fixes and enhancements:**
 
+- Fix regression in `iss` and `aud` claim validation [#619](https://github.com/jwt/ruby-jwt/pull/619) ([@anakinj](https://github.com/anakinj))
 - Your contribution here
 
 ## [v2.9.0](https://github.com/jwt/ruby-jwt/tree/v2.9.0) (2024-09-15)

lib/jwt/claims.rb

@@ -17,10 +17,10 @@ module Claims
     VERIFIERS = {
       verify_expiration: ->(options) { Claims::Expiration.new(leeway: options[:exp_leeway] || options[:leeway]) },
       verify_not_before: ->(options) { Claims::NotBefore.new(leeway: options[:nbf_leeway] || options[:leeway]) },
-      verify_iss: ->(options) { Claims::Issuer.new(issuers: options[:iss]) },
+      verify_iss: ->(options) { options[:iss] && Claims::Issuer.new(issuers: options[:iss]) },
       verify_iat: ->(*) { Claims::IssuedAt.new },
       verify_jti: ->(options) { Claims::JwtId.new(validator: options[:verify_jti]) },
-      verify_aud: ->(options) { Claims::Audience.new(expected_audience: options[:aud]) },
+      verify_aud: ->(options) { options[:aud] && Claims::Audience.new(expected_audience: options[:aud]) },
       verify_sub: ->(options) { options[:sub] && Claims::Subject.new(expected_subject: options[:sub]) },
       required_claims: ->(options) { Claims::Required.new(required_claims: options[:required_claims]) }
     }.freeze