diff --git a/connectivity/nanostack/sal-stack-nanostack/source/6LoWPAN/CMakeLists.txt b/connectivity/nanostack/sal-stack-nanostack/source/6LoWPAN/CMakeLists.txt
index 73699d7d6e..503f8f7e64 100644
--- a/connectivity/nanostack/sal-stack-nanostack/source/6LoWPAN/CMakeLists.txt
+++ b/connectivity/nanostack/sal-stack-nanostack/source/6LoWPAN/CMakeLists.txt
@@ -83,6 +83,7 @@ target_sources(mbed-nanostack-sal_stack
 
         ws/ws_bbr_api.c
         ws/ws_bootstrap.c
+        ws/ws_bootstrap_6lbr.c
         ws/ws_bootstrap_ffn.c
         ws/ws_bootstrap_lfn.c
         ws/ws_cfg_settings.c