diff --git a/tests/include/test/ssl_helpers.h b/tests/include/test/ssl_helpers.h
index 1957043..f997c18 100644
--- a/tests/include/test/ssl_helpers.h
+++ b/tests/include/test/ssl_helpers.h
@@ -456,6 +456,12 @@
         }                                       \
     } while (0)
 
+#if MBEDTLS_SSL_CID_OUT_LEN_MAX > MBEDTLS_SSL_CID_IN_LEN_MAX
+#define SSL_CID_LEN_MIN MBEDTLS_SSL_CID_IN_LEN_MAX
+#else
+#define SSL_CID_LEN_MIN MBEDTLS_SSL_CID_OUT_LEN_MAX
+#endif
+
 int mbedtls_test_ssl_build_transforms(mbedtls_ssl_transform *t_in,
                                       mbedtls_ssl_transform *t_out,
                                       int cipher_type, int hash_id,