diff --git a/nyacme/config.py b/nyacme/config.py
index c67e3b0..a915c13 100644
--- a/nyacme/config.py
+++ b/nyacme/config.py
@@ -59,7 +59,7 @@ def config_parse_secret(raw: Any) -> Secret:
     if type(raw) is str:
         return raw
     if type(raw) is dict:
-        for k, v in raw:
+        for k, v in raw.items():
             if type(k) is not str:
                 raise TypeError(f'invalid type for secret name: expected str, got {type(k).__name__}')
             if type(v) is not str: