diff --git a/lib/request/connect.py b/lib/request/connect.py
index 9cb0f1abf..1f7acc225 100644
--- a/lib/request/connect.py
+++ b/lib/request/connect.py
@@ -569,7 +569,7 @@ class Connect:
                 # throughly without safe chars (especially & and =)
                 # addendum: as we support url encoding in tampering
                 # functions therefore we need to use % as a safe char
-                if place != PLACE.URI or (value and '?' in value and value.find('?') < value.find(payload)):
+                if place != PLACE.URI or (value and payload and '?' in value and value.find('?') < value.find(payload)):
                     payload = urlencode(payload, "%", False, True)
                     value = agent.replacePayload(value, payload)
             elif place == PLACE.SOAP: