diff --git a/lib/decoding/osmocom/gsm/CMakeLists.txt b/lib/decoding/osmocom/gsm/CMakeLists.txt
index 945d1c2..93ef28a 100644
--- a/lib/decoding/osmocom/gsm/CMakeLists.txt
+++ b/lib/decoding/osmocom/gsm/CMakeLists.txt
@@ -2,5 +2,6 @@
 a5.c
 auth_core.c
 gsm48_ie.c
+gsm_utils.c
 kasumi.c
 )