diff --git a/lib/ykpiv.c b/lib/ykpiv.c
index 2e416ce..854ccc1 100644
--- a/lib/ykpiv.c
+++ b/lib/ykpiv.c
@@ -1849,6 +1849,7 @@ ykpiv_rc ykpiv_auth_verifyresponse(ykpiv_state *state, uint8_t *response, const
 
 Cleanup:
 
+  yc_memzero(&apdu, sizeof(apdu));
   _ykpiv_end_transaction(state);
   return res;
 }