diff --git a/src/manage.c b/src/manage.c
index 3afde994..de4f6fd7 100644
--- a/src/manage.c
+++ b/src/manage.c
@@ -407,6 +407,11 @@ void manage_window(xcb_window_t window, xcb_get_window_attributes_cookie_t cooki
                 Con *next_transient = con_by_window_id(transient_win->transient_for);
                 if (next_transient == NULL)
                     break;
+                /* Some clients (e.g. x11-ssh-askpass) actually set
+                 * WM_TRANSIENT_FOR to their own window id, so break instead of
+                 * looping endlessly. */
+                if (transient_win == next_transient->window)
+                    break;
                 transient_win = next_transient->window;
             }
         }
diff --git a/src/render.c b/src/render.c
index f996d964..2cc50d57 100644
--- a/src/render.c
+++ b/src/render.c
@@ -286,7 +286,15 @@ void render_con(Con *con, bool render_fullscreen) {
                             is_transient_for = true;
                             break;
                         }
-                        transient_con = con_by_window_id(transient_con->window->transient_for);
+                        Con *next_transient = con_by_window_id(transient_con->window->transient_for);
+                        if (next_transient == NULL)
+                            break;
+                        /* Some clients (e.g. x11-ssh-askpass) actually set
+                         * WM_TRANSIENT_FOR to their own window id, so break instead of
+                         * looping endlessly. */
+                        if (transient_con == next_transient)
+                            break;
+                        transient_con = next_transient;
                     }
 
                     if (!is_transient_for)