diff --git a/sys/net/gnrc/transport_layer/tcp/gnrc_tcp_rcvbuf.c b/sys/net/gnrc/transport_layer/tcp/gnrc_tcp_rcvbuf.c
index e06fc5de0d..4663eb6d90 100644
--- a/sys/net/gnrc/transport_layer/tcp/gnrc_tcp_rcvbuf.c
+++ b/sys/net/gnrc/transport_layer/tcp/gnrc_tcp_rcvbuf.c
@@ -24,7 +24,7 @@
 /**
  * @brief Internal struct holding receive buffers.
  */
-rcvbuf_t _static_buf;
+static rcvbuf_t _static_buf;
 
 /**
  * @brief Initializes all receive buffers.