Index: apps/app_stack.c
===================================================================
--- apps/app_stack.c	(revision 406910)
+++ apps/app_stack.c	(working copy)
@@ -645,6 +645,12 @@
 	}
 
 	AST_STANDARD_RAW_ARGS(args, data);
+
+	if (ast_strlen_zero(args.n) || ast_strlen_zero(args.name)) {
+		ast_log(LOG_ERROR, "LOCAL_PEEK requires parameters n and varname\n");
+		return -1;
+	}
+
 	n = atoi(args.n);
 	*buf = '\0';
 
@@ -684,6 +690,11 @@
 	data = ast_strdupa(data);
 	AST_STANDARD_APP_ARGS(args, data);
 
+	if (ast_strlen_zero(args.n) || ast_strlen_zero(args.which)) {
+		ast_log(LOG_ERROR, "STACK_PEEK requires parameters n and which\n");
+		return -1;
+	}
+
 	n = atoi(args.n);
 	if (n <= 0) {
 		ast_log(LOG_ERROR, "STACK_PEEK must be called with a positive peek value\n");