diff --git a/src/map.c b/src/map.c
index a4fd54b..e3b0f2a 100644
--- a/src/map.c
+++ b/src/map.c
@@ -149,6 +149,7 @@
 	default:
 		memprintf(err, "map: internal haproxy error: no default parse case for the input type <%d>.",
 		          conv->out_type);
+		free(desc);
 		return 0;
 	}