diff --git a/src/proxy.c b/src/proxy.c
index f1d9d7ab0..8309c949e 100644
--- a/src/proxy.c
+++ b/src/proxy.c
@@ -218,6 +218,7 @@ void free_proxy(struct proxy *p)
 	free(p->server_state_file_name);
 	free(p->capture_name);
 	istfree(&p->monitor_uri);
+	istfree(&p->server_id_hdr_name);
 	free(p->rdp_cookie_name);
 	free(p->invalid_rep);
 	free(p->invalid_req);