diff --git a/libfreefare/mifare_desfire.c b/libfreefare/mifare_desfire.c
index e1495c1..543d80a 100644
--- a/libfreefare/mifare_desfire.c
+++ b/libfreefare/mifare_desfire.c
@@ -1235,6 +1235,8 @@ mifare_desfire_get_iso_file_ids (MifareTag tag, uint16_t **files, size_t *count)
 	(*files)[i] = le16toh (*(uint16_t *)(p + (2*i)));
     }
 
+    free (data);
+
     return 0;
 }