diff --git a/addons/namingng.py b/addons/namingng.py
index 73f1b08ec..a543669d5 100755
--- a/addons/namingng.py
+++ b/addons/namingng.py
@@ -132,7 +132,7 @@ def process(dumpfiles, configfile, debugprint=False):
 
                         if conf["skip_one_char_variables"] and len(var.nameToken.str) == 1:
                             continue
-                        if varType in conf["var_prefixes"]:
+                        if varType in conf.get("var_prefixes",{}):
                             if not var.nameToken.str.startswith(conf["var_prefixes"][varType]):
                                 errors.append(reportError(
                                                     var.typeStartToken.file,
@@ -192,7 +192,7 @@ def process(dumpfiles, configfile, debugprint=False):
                         if debugprint:
                             print("\t:: {} {}".format(retval, token.function.name))
 
-                        if retval and retval in conf["function_prefixes"]:
+                        if retval and retval in conf.get("function_prefixes",{}):
                             if not token.function.name.startswith(conf["function_prefixes"][retval]):
                                 errors.append(reportError(
                                     token.file, token.linenr, 'style', 'Function ' + token.function.name + ' violates naming convention'))