1 files changed, 1 insertions, 1 deletions
diff --git a/synapse/events/validator.py b/synapse/events/validator.py
index 4d459c17f1..cf86934968 100644
--- a/synapse/events/validator.py
+++ b/synapse/events/validator.py
@@ -55,7 +55,7 @@ class EventValidator:
         ]
 
         for k in required:
-            if not hasattr(event, k):
+            if k not in event:
                 raise SynapseError(400, "Event does not have key %s" % (k,))
 
         # Check that the following keys have string values