diff --git a/app/lib/activitypub/linked_data_signature.rb b/app/lib/activitypub/linked_data_signature.rb
index 7173aed19..4483339a9 100644
--- a/app/lib/activitypub/linked_data_signature.rb
+++ b/app/lib/activitypub/linked_data_signature.rb
@@ -6,7 +6,7 @@ class ActivityPub::LinkedDataSignature
   CONTEXT = 'https://w3id.org/identity/v1'
 
   def initialize(json)
-    @json = json
+    @json = json.with_indifferent_access
   end
 
   def verify_account!