diff --git a/main/configuration-parser.y b/main/configuration-parser.y
index a201ce5eb46..852e4dc2916 100644
--- a/main/configuration-parser.y
+++ b/main/configuration-parser.y
@@ -548,6 +548,7 @@ string_or_value:
 	|	CFG_TRUE { $$ = $1; }
 	|	CFG_FALSE { $$ = $1; }
 	|	'\n' { $$.value.str.val = strdup(""); $$.value.str.len=0; $$.type = IS_STRING; }
+	|	'\0' { $$.value.str.val = strdup(""); $$.value.str.len=0; $$.type = IS_STRING; }
 ;
 
 expr: