diff -urNp -x '*.orig' mutt-2.0.6.org/signature.c mutt-2.0.6/signature.c
--- mutt-2.0.6.org/signature.c	2021-04-18 19:23:40.820045368 +0200
+++ mutt-2.0.6/signature.c	2021-04-18 19:23:40.966713972 +0200
@@ -290,7 +290,7 @@ static SIG_LIST *sig_search_filter (MUTT
   char* searchBuf = menu->menu >= 0 && menu->menu < MENU_MAX ?
                     SearchBuffers[menu->menu] : NULL;
 
-  snprintf (buf, sizeof(buf), searchBuf ? searchBuf : "");
+  snprintf (buf, sizeof(buf), "%s", searchBuf ? searchBuf : "");
   if (mutt_get_field (_("Search for: "), buf,
 		      sizeof (buf), MUTT_CLEAR) != 0 || !buf[0])
     return (NULL);