diff --git a/manager/knot_resolver_manager/datamodel/types/files.py b/manager/knot_resolver_manager/datamodel/types/files.py
index a8158e6e4..4c6e7186f 100644
--- a/manager/knot_resolver_manager/datamodel/types/files.py
+++ b/manager/knot_resolver_manager/datamodel/types/files.py
@@ -179,9 +179,12 @@ def accessible(perm: _PermissionMode) -> bool:
             return bool(dest_mode & chflags[perm][1])
         return bool(dest_mode & chflags[perm][2])
 
-    for perm in perm_mode:
-        if not accessible(perm):
-            return False
+    # __iter__ for class enum.Flag added in python3.11
+    # 'for perm in perm_mode:' failes for <=python3.11
+    for perm in _PermissionMode:
+        if perm in perm_mode:
+            if not accessible(perm):
+                return False
     return True