diff --git a/features/lwipstack/lwip/src/netif/ppp/lwip_utils.c b/features/lwipstack/lwip/src/netif/ppp/lwip_utils.c
index fc8791170c..dd18ac779d 100644
--- a/features/lwipstack/lwip/src/netif/ppp/lwip_utils.c
+++ b/features/lwipstack/lwip/src/netif/ppp/lwip_utils.c
@@ -603,7 +603,7 @@ void ppp_print_string(const u_char *p, int len, void (*printer) (void *, const c
  * ppp_logit - does the hard work for fatal et al.
  */
 static void ppp_logit(int level, const char *fmt, va_list args) {
-    char buf[1024];
+    char buf[256];
 
     ppp_vslprintf(buf, sizeof(buf), fmt, args);
     ppp_log_write(level, buf);