From 483917529f452d98cdb54bb097322259bbf1cdc7 Mon Sep 17 00:00:00 2001
From: Christoph Zurnieden <czurnieden@gmx.com>
Date: Mon, 20 Apr 2026 14:43:31 +0200
Subject: [PATCH] Input check added

---
 mp_from_sbin.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/mp_from_sbin.c b/mp_from_sbin.c
index 26eb0f120..2d32a1d8b 100644
--- a/mp_from_sbin.c
+++ b/mp_from_sbin.c
@@ -8,6 +8,9 @@ mp_err mp_from_sbin(mp_int *a, const uint8_t *buf, size_t size)
 {
    mp_err err;
 
+   if (size == 0) {
+      return MP_VAL;
+   }
    /* read magnitude */
    if ((err = mp_from_ubin(a, buf + 1, size - 1u)) != MP_OKAY) {
       return err;