diff --git a/src/check.c b/src/check.c
index 3d03d6aa8..c994108ac 100644
--- a/src/check.c
+++ b/src/check.c
@@ -1574,7 +1574,7 @@ void free_check(struct check *check)
 	}
 
 	ha_free(&check->pool_conn_name);
-
+	ha_free(&check->alpn_str);
 	task_destroy(check->task);
 
 	check_release_buf(check, &check->bi);
diff --git a/src/server.c b/src/server.c
index d4ae2e895..ccaa1665a 100644
--- a/src/server.c
+++ b/src/server.c
@@ -2901,8 +2901,15 @@ void srv_settings_cpy(struct server *srv, const struct server *src, int srv_tmpl
 	srv->check.use_ssl            = src->check.use_ssl;
 	srv->check.port               = src->check.port;
 	srv->check.sni                = src->check.sni;
-	srv->check.alpn_str           = src->check.alpn_str;
-	srv->check.alpn_len           = src->check.alpn_len;
+	if (src->check.alpn_str) {
+		srv->check.alpn_str = malloc(src->check.alpn_len);
+		if (srv->check.alpn_str) {
+			memcpy(srv->check.alpn_str, src->check.alpn_str,
+			       src->check.alpn_len);
+			srv->check.alpn_len = src->check.alpn_len;
+		}
+	}
+
 	if (!(srv->flags & SRV_F_RHTTP))
 		srv->check.reuse_pool = src->check.reuse_pool;
 	if (src->check.pool_conn_name)