diff --git a/hw/usb/dev-smartcard-reader.c b/hw/usb/dev-smartcard-reader.c
index 89e11b68c4..1325ea1659 100644
--- a/hw/usb/dev-smartcard-reader.c
+++ b/hw/usb/dev-smartcard-reader.c
@@ -967,7 +967,7 @@ static void ccid_on_apdu_from_guest(USBCCIDState *s, CCID_XferBlock *recv)
     DPRINTF(s, 1, "%s: seq %d, len %d\n", __func__,
                 recv->hdr.bSeq, len);
     ccid_add_pending_answer(s, (CCID_Header *)recv);
-    if (s->card) {
+    if (s->card && len <= BULK_OUT_DATA_SIZE) {
         ccid_card_apdu_from_guest(s->card, recv->abData, len);
     } else {
         DPRINTF(s, D_WARN, "warning: discarded apdu\n");