diff --git a/src/tests/hnb-test-ranap.c b/src/tests/hnb-test-ranap.c
index fe7db48..3db876c 100644
--- a/src/tests/hnb-test-ranap.c
+++ b/src/tests/hnb-test-ranap.c
@@ -16,7 +16,7 @@
 				  struct ranap_message_s *ranap_msg)
 {
 	int len;
-	char *data;
+	uint8_t *data;
 	RANAP_PermittedIntegrityProtectionAlgorithms_t *algs;
 	RANAP_IntegrityProtectionAlgorithm_t *first_alg;