diff --git a/src/libsodium/crypto_auth/hmacsha256/cp/hmac_hmacsha256.c b/src/libsodium/crypto_auth/hmacsha256/cp/hmac_hmacsha256.c
index 9cd69ac3..b2e7a789 100644
--- a/src/libsodium/crypto_auth/hmacsha256/cp/hmac_hmacsha256.c
+++ b/src/libsodium/crypto_auth/hmacsha256/cp/hmac_hmacsha256.c
@@ -66,6 +66,7 @@ crypto_auth_hmacsha256_init(crypto_auth_hmacsha256_state *state,
     }
     crypto_hash_sha256_update(&state->octx, pad, 64);
 
+    sodium_memzero((void *) pad, sizeof pad);
     sodium_memzero((void *) khash, sizeof khash);
 
     return 0;