--- a/src/event/ngx_event_openssl.c
+++ b/src/event/ngx_event_openssl.c
@@ -1051,7 +1051,7 @@ cleanup:
                            ngx_close_file_n " \"%s\" failed", file->data);
     }
 
-    ngx_memzero(buf, NGX_SSL_PASSWORD_BUFFER_SIZE);
+    ngx_explicit_memzero(buf, NGX_SSL_PASSWORD_BUFFER_SIZE);
 
     return passwords;
 }
@@ -1068,7 +1068,7 @@ ngx_ssl_passwords_cleanup(void *data)
     pwd = passwords->elts;
 
     for (i = 0; i < passwords->nelts; i++) {
-        ngx_memzero(pwd[i].data, pwd[i].len);
+        ngx_explicit_memzero(pwd[i].data, pwd[i].len);
     }
 }