diff --git a/server.py b/server.py
index 6190e2e8bf786686cc92cf116aeed6ce3a19a224..91c79e5407c07eed159bd98fd4a10b1e40786b49 100644
--- a/server.py
+++ b/server.py
@@ -146,7 +146,7 @@ def checkperm(perms, username=None, password=None):
 			if 'X-Real-IP' not in request.headers:
 				continue
 			ip = ip_address(request.headers['X-Real-IP'])
-			for net in RWTH_IP_RANGES:
+			for net in config['RWTH_IP_RANGES']:
 				if ip in ip_network(net):
 					return True
 	return False