diff --git a/src/ssl_sock.c b/src/ssl_sock.c
index 6513760ac..bcfa3e712 100644
--- a/src/ssl_sock.c
+++ b/src/ssl_sock.c
@@ -4934,8 +4934,9 @@ int ssl_sock_prepare_ctx(struct bind_conf *bind_conf, struct ssl_bind_conf *ssl_
 	conf_ciphersuites = (ssl_conf && ssl_conf->ciphersuites) ? ssl_conf->ciphersuites : bind_conf->ssl_conf.ciphersuites;
 	if (conf_ciphersuites &&
 	    !SSL_CTX_set_ciphersuites(ctx, conf_ciphersuites)) {
-		memprintf(err, "%sProxy '%s': unable to set TLS 1.3 cipher suites to '%s' for bind '%s' at [%s:%d].\n",
-		          *err ? *err : "", curproxy->id, conf_ciphersuites, bind_conf->arg, bind_conf->file, bind_conf->line);
+		if (err)
+			memprintf(err, "%sProxy '%s': unable to set TLS 1.3 cipher suites to '%s' for bind '%s' at [%s:%d].\n",
+				  *err ? *err : "", curproxy->id, conf_ciphersuites, bind_conf->arg, bind_conf->file, bind_conf->line);
 		cfgerr |= ERR_ALERT | ERR_FATAL;
 	}
 #endif
@@ -5034,8 +5035,9 @@ int ssl_sock_prepare_ctx(struct bind_conf *bind_conf, struct ssl_bind_conf *ssl_
 	conf_curves = (ssl_conf && ssl_conf->curves) ? ssl_conf->curves : bind_conf->ssl_conf.curves;
 	if (conf_curves) {
 		if (!SSL_CTX_set1_curves_list(ctx, conf_curves)) {
-			memprintf(err, "%sProxy '%s': unable to set SSL curves list to '%s' for bind '%s' at [%s:%d].\n",
-			          *err ? *err : "", curproxy->id, conf_curves, bind_conf->arg, bind_conf->file, bind_conf->line);
+			if (err)
+				memprintf(err, "%sProxy '%s': unable to set SSL curves list to '%s' for bind '%s' at [%s:%d].\n",
+					  *err ? *err : "", curproxy->id, conf_curves, bind_conf->arg, bind_conf->file, bind_conf->line);
 			cfgerr |= ERR_ALERT | ERR_FATAL;
 		}
 #if defined(SSL_CTX_set_ecdh_auto)
@@ -5064,8 +5066,9 @@ int ssl_sock_prepare_ctx(struct bind_conf *bind_conf, struct ssl_bind_conf *ssl_
 
 		i = OBJ_sn2nid(ecdhe);
 		if (!i || ((ecdh = EC_KEY_new_by_curve_name(i)) == NULL)) {
-			memprintf(err, "%sProxy '%s': unable to set elliptic named curve to '%s' for bind '%s' at [%s:%d].\n",
-			          *err ? *err : "", curproxy->id, ecdhe, bind_conf->arg, bind_conf->file, bind_conf->line);
+			if (err)
+				memprintf(err, "%sProxy '%s': unable to set elliptic named curve to '%s' for bind '%s' at [%s:%d].\n",
+					  *err ? *err : "", curproxy->id, ecdhe, bind_conf->arg, bind_conf->file, bind_conf->line);
 			cfgerr |= ERR_ALERT | ERR_FATAL;
 		}
 		else {