Index: obuspa-10.0.0.1/src/core/mqtt.c
===================================================================
--- obuspa-10.0.0.1.orig/src/core/mqtt.c
+++ obuspa-10.0.0.1/src/core/mqtt.c
@@ -259,6 +259,8 @@ void MqttSubscriptionDestroy(mqtt_subscr
 #define DEFINE_MQTT_TrustCertVerifyCallbackIndex(index) \
 int MQTT_TrustCertVerifyCallback_##index (int preverify_ok, X509_STORE_CTX *x509_ctx) \
 {\
+    if (index >= MAX_MQTT_CLIENTS) \
+	    return 0; \
     return DEVICE_SECURITY_TrustCertVerifyCallbackWithCertChain(preverify_ok, x509_ctx, &mqtt_clients[index].cert_chain);\
 }
 
@@ -269,6 +271,11 @@ DEFINE_MQTT_TrustCertVerifyCallbackIndex
 DEFINE_MQTT_TrustCertVerifyCallbackIndex(2);
 DEFINE_MQTT_TrustCertVerifyCallbackIndex(3);
 DEFINE_MQTT_TrustCertVerifyCallbackIndex(4);
+DEFINE_MQTT_TrustCertVerifyCallbackIndex(5);
+DEFINE_MQTT_TrustCertVerifyCallbackIndex(6);
+DEFINE_MQTT_TrustCertVerifyCallbackIndex(7);
+DEFINE_MQTT_TrustCertVerifyCallbackIndex(8);
+DEFINE_MQTT_TrustCertVerifyCallbackIndex(9);
 // Add more, with incrementing indexes here, if you change MAX_MQTT_CLIENTS
 
 //------------------------------------------------------------------------------------
@@ -279,10 +286,15 @@ ssl_verify_callback_t* mqtt_verify_callb
     MQTT_TrustCertVerifyCallbackIndex(2),
     MQTT_TrustCertVerifyCallbackIndex(3),
     MQTT_TrustCertVerifyCallbackIndex(4),
+    MQTT_TrustCertVerifyCallbackIndex(5),
+    MQTT_TrustCertVerifyCallbackIndex(6),
+    MQTT_TrustCertVerifyCallbackIndex(7),
+    MQTT_TrustCertVerifyCallbackIndex(8),
+    MQTT_TrustCertVerifyCallbackIndex(9),
     // Add more, with incrementing indexes here, if you change MAX_MQTT_CLIENTS
 };
 
-USP_COMPILEASSERT( ((sizeof(mqtt_verify_callbacks)/sizeof(ssl_verify_callback_t*)) == MAX_MQTT_CLIENTS),
+USP_COMPILEASSERT( ((sizeof(mqtt_verify_callbacks)/sizeof(ssl_verify_callback_t*)) >= MAX_MQTT_CLIENTS),
         "There must be MAX_MQTT_CLIENTS callbacks defined");
 
 /*********************************************************************//**