diff --git a/src/libsodium/crypto_box/crypto_box_seal.c b/src/libsodium/crypto_box/crypto_box_seal.c
index 338e2893..0d261d86 100644
--- a/src/libsodium/crypto_box/crypto_box_seal.c
+++ b/src/libsodium/crypto_box/crypto_box_seal.c
@@ -35,6 +35,8 @@ crypto_box_seal(unsigned char *c, const unsigned char *m,
     _crypto_box_seal_nonce(nonce, epk, pk);
     ret = crypto_box_easy(c + crypto_box_PUBLICKEYBYTES, m, mlen,
                           nonce, pk, esk);
+    sodium_memzero(nonce, sizeof nonce);
+    sodium_memzero(epk, sizeof epk);
     sodium_memzero(esk, sizeof esk);
 
     return ret;