diff --git a/include/mbedtls/config.h b/include/mbedtls/config.h
index a95ec02..2c7bed2 100644
--- a/include/mbedtls/config.h
+++ b/include/mbedtls/config.h
@@ -3912,7 +3912,7 @@
  *            on it, and considering stronger message digests instead.
  *
  */
-#define MBEDTLS_TLS_DEFAULT_ALLOW_SHA1_IN_KEY_EXCHANGE
+//#define MBEDTLS_TLS_DEFAULT_ALLOW_SHA1_IN_KEY_EXCHANGE
 
 /**
  * Uncomment the macro to let mbed TLS use your alternate implementation of