diff --git a/include/mbedtls/config.h b/include/mbedtls/config.h
index fff4240c0..d9ccbb4b4 100644
--- a/include/mbedtls/config.h
+++ b/include/mbedtls/config.h
@@ -2249,7 +2249,7 @@
  * Requires: MBEDTLS_AES_C or MBEDTLS_DES_C
  *
  */
-//#define MBEDTLS_CMAC_C
+#define MBEDTLS_CMAC_C
 
 /**
  * \def MBEDTLS_CTR_DRBG_C