diff --git a/components/tcp_transport/transport_ws.c b/components/tcp_transport/transport_ws.c
index f7434aa02fb..b7db2efc08a 100644
--- a/components/tcp_transport/transport_ws.c
+++ b/components/tcp_transport/transport_ws.c
@@ -291,7 +291,7 @@ static int ws_connect(esp_transport_handle_t t, const char *host, int port, int
         }
         header_len += len;
         ws->buffer_len = header_len;
-        ws->buffer[header_len] = '\0'; // We will mark the end of the header to ensure that strstr operations for parsing the headers don't fail.
+        ws->buffer[header_len - 1] = '\0'; // We will mark the end of the header to ensure that strstr operations for parsing the headers don't fail.
         ESP_LOGD(TAG, "Read header chunk %d, current header size: %d", len, header_len);
     } while (NULL == strstr(ws->buffer, delimiter) && header_len < WS_BUFFER_SIZE);