diff --git a/.ruby-version b/.ruby-version
index 47b322c..2aa5131 100644
--- a/.ruby-version
+++ b/.ruby-version
@@ -1 +1 @@
-3.4.1
+3.4.7
diff --git a/lib/openapi_contracts/rspec.rb b/lib/openapi_contracts/rspec.rb
index b183e10..966ee2b 100644
--- a/lib/openapi_contracts/rspec.rb
+++ b/lib/openapi_contracts/rspec.rb
@@ -29,7 +29,9 @@
 
   def with_http_status(status)
     if status.is_a? Symbol
-      @status = Rack::Utils::SYMBOL_TO_STATUS_CODE[status]
+      @status = Rack::Utils::SYMBOL_TO_STATUS_CODE.fetch(status) do
+        raise ArgumentError, "Unknown status #{status.inspect}"
+      end
     else
       @status = status
     end
diff --git a/spec/integration/rspec_spec.rb b/spec/integration/rspec_spec.rb
index cd11408..d3464b7 100644
--- a/spec/integration/rspec_spec.rb
+++ b/spec/integration/rspec_spec.rb
@@ -90,6 +90,14 @@
     it { is_expected.to match_openapi_doc(doc).with_http_status(:bad_request) }
   end
 
+  context 'when using unsupported status' do
+    it {
+      expect {
+        expect(subject).to match_openapi_doc(doc).with_http_status(:does_not_exist_in_rack)
+      }.to raise_error(ArgumentError, 'Unknown status :does_not_exist_in_rack')
+    }
+  end
+
   context 'when using dynamic paths' do
     let(:path) { '/messages/ef278ab2' }
     let(:response_json) do