diff --git a/src/AsyncTCP.cpp b/src/AsyncTCP.cpp
index 8b4bc16..d433c0c 100644
--- a/src/AsyncTCP.cpp
+++ b/src/AsyncTCP.cpp
@@ -39,6 +39,26 @@ extern "C"{
 #include <NetworkInterface.h>
 #endif
 
+#define TAG "AsyncTCP"
+
+// https://github.com/espressif/arduino-esp32/issues/10526
+#ifdef CONFIG_LWIP_TCPIP_CORE_LOCKING
+#define TCP_MUTEX_LOCK()                                \
+  if (!sys_thread_tcpip(LWIP_CORE_LOCK_QUERY_HOLDER)) { \
+    ESP_LOGE(TAG, "LOCK_TCPIP_CORE @ %s:%d", __FILE__, __LINE__); \
+    LOCK_TCPIP_CORE();                                  \
+  }
+
+#define TCP_MUTEX_UNLOCK()                             \
+  if (sys_thread_tcpip(LWIP_CORE_LOCK_QUERY_HOLDER)) { \
+    ESP_LOGE(TAG, "UNLOCK_TCPIP_CORE @ %s:%d", __FILE__, __LINE__); \
+    UNLOCK_TCPIP_CORE();                               \
+  }
+#else  // CONFIG_LWIP_TCPIP_CORE_LOCKING
+#define TCP_MUTEX_LOCK()
+#define TCP_MUTEX_UNLOCK()
+#endif  // CONFIG_LWIP_TCPIP_CORE_LOCKING
+
 #define INVALID_CLOSED_SLOT -1
 
 /*
@@ -600,11 +620,13 @@ AsyncClient::AsyncClient(tcp_pcb* pcb)
     _closed_slot = INVALID_CLOSED_SLOT;
     if(_pcb){
         _rx_last_packet = millis();
+        TCP_MUTEX_LOCK();
         tcp_arg(_pcb, this);
         tcp_recv(_pcb, &_tcp_recv);
         tcp_sent(_pcb, &_tcp_sent);
         tcp_err(_pcb, &_tcp_error);
         tcp_poll(_pcb, &_tcp_poll, 1);
+        TCP_MUTEX_UNLOCK();
         if(!_allocate_closed_slot()) {
             _close();
         }
@@ -631,11 +653,13 @@ AsyncClient& AsyncClient::operator=(const AsyncClient& other){
     _closed_slot = other._closed_slot;
     if (_pcb) {
         _rx_last_packet = millis();
+        TCP_MUTEX_LOCK();
         tcp_arg(_pcb, this);
         tcp_recv(_pcb, &_tcp_recv);
         tcp_sent(_pcb, &_tcp_sent);
         tcp_err(_pcb, &_tcp_error);
         tcp_poll(_pcb, &_tcp_poll, 1);
+        TCP_MUTEX_UNLOCK();
     }
     return *this;
 }
@@ -722,8 +746,10 @@ bool AsyncClient::_connect(ip_addr_t addr, uint16_t port){
         return false;
     }
 
+    TCP_MUTEX_LOCK();
     tcp_pcb* pcb = tcp_new_ip_type(addr.type);
     if (!pcb){
+        TCP_MUTEX_UNLOCK();
         log_e("pcb == NULL");
         return false;
     }
@@ -733,6 +759,7 @@ bool AsyncClient::_connect(ip_addr_t addr, uint16_t port){
     tcp_recv(pcb, &_tcp_recv);
     tcp_sent(pcb, &_tcp_sent);
     tcp_poll(pcb, &_tcp_poll, 1);
+    TCP_MUTEX_UNLOCK();
     esp_err_t err =_tcp_connect(pcb, _closed_slot, &addr, port,(tcp_connected_fn)&_tcp_connected);
     return err == ESP_OK;
 }
@@ -863,11 +890,13 @@ int8_t AsyncClient::_close(){
     //ets_printf("X: 0x%08x\n", (uint32_t)this);
     int8_t err = ERR_OK;
     if(_pcb) {
+        TCP_MUTEX_LOCK();
         tcp_arg(_pcb, NULL);
         tcp_sent(_pcb, NULL);
         tcp_recv(_pcb, NULL);
         tcp_err(_pcb, NULL);
         tcp_poll(_pcb, NULL, 0);
+        TCP_MUTEX_UNLOCK();
         _tcp_clear_events(this);
         err = _tcp_close(_pcb, _closed_slot);
         if(err != ERR_OK) {
@@ -928,6 +957,7 @@ int8_t AsyncClient::_connected(tcp_pcb* pcb, int8_t err){
 
 void AsyncClient::_error(int8_t err) {
     if(_pcb){
+        TCP_MUTEX_LOCK();
         tcp_arg(_pcb, NULL);
         if(_pcb->state == LISTEN) {
             tcp_sent(_pcb, NULL);
@@ -935,6 +965,7 @@ void AsyncClient::_error(int8_t err) {
             tcp_err(_pcb, NULL);
             tcp_poll(_pcb, NULL, 0);
         }
+        TCP_MUTEX_UNLOCK();
         _free_closed_slot();
         _pcb = NULL;
     }
@@ -952,6 +983,7 @@ int8_t AsyncClient::_lwip_fin(tcp_pcb* pcb, int8_t err) {
         log_d("0x%08x != 0x%08x", (uint32_t)pcb, (uint32_t)_pcb);
         return ERR_OK;
     }
+    TCP_MUTEX_LOCK();
     tcp_arg(_pcb, NULL);
     if(_pcb->state == LISTEN) {
         tcp_sent(_pcb, NULL);
@@ -959,6 +991,7 @@ int8_t AsyncClient::_lwip_fin(tcp_pcb* pcb, int8_t err) {
         tcp_err(_pcb, NULL);
         tcp_poll(_pcb, NULL, 0);
     }
+    TCP_MUTEX_UNLOCK();
     if(tcp_close(_pcb) != ERR_OK) {
         tcp_abort(_pcb);
     }
@@ -1461,7 +1494,9 @@ void AsyncServer::begin(){
         return;
     }
     int8_t err;
+    TCP_MUTEX_LOCK();
     _pcb = tcp_new_ip_type(_bind4 && _bind6 ? IPADDR_TYPE_ANY : (_bind6 ? IPADDR_TYPE_V6 : IPADDR_TYPE_V4));
+    TCP_MUTEX_UNLOCK();
     if (!_pcb){
         log_e("_pcb == NULL");
         return;
@@ -1493,14 +1528,18 @@ void AsyncServer::begin(){
         log_e("listen_pcb == NULL");
         return;
     }
+    TCP_MUTEX_LOCK();
     tcp_arg(_pcb, (void*) this);
     tcp_accept(_pcb, &_s_accept);
+    TCP_MUTEX_UNLOCK();
 }
 
 void AsyncServer::end(){
     if(_pcb){
+        TCP_MUTEX_LOCK();
         tcp_arg(_pcb, NULL);
         tcp_accept(_pcb, NULL);
+        TCP_MUTEX_UNLOCK();
         if(tcp_close(_pcb) != ERR_OK){
             _tcp_abort(_pcb, -1);
         }