diff --git a/components/lwip/apps/dhcpserver/dhcpserver.c b/components/lwip/apps/dhcpserver/dhcpserver.c
index e7262d96829..9b7062a9301 100644
--- a/components/lwip/apps/dhcpserver/dhcpserver.c
+++ b/components/lwip/apps/dhcpserver/dhcpserver.c
@@ -1174,11 +1174,19 @@ static s16_t parse_msg(dhcps_t *dhcps, struct dhcps_msg *m, u16_t len)
             pnode = NULL;
         } else {
             pdhcps_pool = (struct dhcps_pool *)mem_calloc(1, sizeof(struct dhcps_pool));
+            if (pdhcps_pool == NULL) {
+                return 0;
+            }
 
             pdhcps_pool->ip.addr = dhcps->client_address.addr;
             memcpy(pdhcps_pool->mac, m->chaddr, sizeof(pdhcps_pool->mac));
             pdhcps_pool->lease_timer = lease_timer;
             pnode = (list_node *)mem_calloc(1, sizeof(list_node));
+            if (pnode == NULL) {
+                mem_free(pdhcps_pool);
+                pdhcps_pool = NULL;
+                return 0;
+            }
 
             pnode->pnode = pdhcps_pool;
             pnode->pnext = NULL;
diff --git a/components/lwip/port/hooks/lwip_default_hooks.c b/components/lwip/port/hooks/lwip_default_hooks.c
index 6c094fdf047..6c7627ccc98 100644
--- a/components/lwip/port/hooks/lwip_default_hooks.c
+++ b/components/lwip/port/hooks/lwip_default_hooks.c
@@ -210,6 +210,9 @@ void dhcp_parse_extra_opts(struct dhcp *dhcp, uint8_t state, uint8_t option, uin
     NETIF_FOREACH(netif) {
       /* find the netif related to this dhcp */
       if (dhcp == netif_dhcp_data(netif)) {
+        if (mtu < 68) { /* RFC 2132 requires MTU >= 68 */
+          return;
+        }
         if (mtu < netif->mtu) {
           netif->mtu = mtu;
           LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_parse_extra_opts(): Negotiated netif MTU is %d\n", netif->mtu));