diff --git a/tests/tcp_cmd.cpp b/tests/tcp_cmd.cpp
index 00ed0fa..b3e2bc2 100644
--- a/tests/tcp_cmd.cpp
+++ b/tests/tcp_cmd.cpp
@@ -202,6 +202,11 @@ static err_t tcp_cmd_recv_new(void* arg, struct tcp_pcb* pcb, struct pbuf* p, er
         tcp_recved(pcb, p->tot_len);
         char* next;
 
+        // Make sure the string is null terminated
+        p->payload = realloc(p->payload, p->len + 1);
+        p->tot_len = p->len + 1;
+        ((char*)(p->payload))[p->len] = '\0';
+        
         remove_newline((char*)(p->payload));
         // Split string into tokens by delimiter (space)
         argv[0] = get_next_token((char*)(p->payload), " ", &next);