diff --git a/src/liblsquic/lsquic_engine.c b/src/liblsquic/lsquic_engine.c
index 41a7a6c..76ab021 100644
--- a/src/liblsquic/lsquic_engine.c
+++ b/src/liblsquic/lsquic_engine.c
@@ -1420,6 +1420,9 @@ lsquic_engine_destroy (lsquic_engine_t *engine)
     }
     lsquic_hash_destroy(engine->conns_hash);
 
+    while ((conn = attq_pop(engine->attq, UINT64_MAX)))
+        (void) engine_decref_conn(engine, conn, LSCONN_ATTQ);
+
     assert(0 == engine->n_conns);
     assert(0 == engine->mini_conns_count);
     if (engine->pr_queue)