diff --git a/testing/misc_tools.c b/testing/misc_tools.c
index dbaa8b3b..08f57588 100644
--- a/testing/misc_tools.c
+++ b/testing/misc_tools.c
@@ -36,5 +36,7 @@ unsigned char * hex_string_to_bin(char hex_string[])
     int i;
     for(i = 0; i < len; ++i, pos+=2)
         sscanf(pos,"%2hhx",&val[i]);
+
+    free(val);
     return val;
 }