icingaweb2/modules/monitoring/application/views/scripts/show/components/customvars.phtml

<?php

if (! $object->customvars) { return; }

foreach ($object->customvars as $name => $value) {
    $name = ucwords(str_replace('_', ' ', strtolower($name)));
    if (preg_match('~(?:pw|pass|community)~', strtolower($name))) {
        $value = '***';
    }
    printf(
        "<tr><th>%s</th><td>%s</td></tr>\n",
        $this->escape($name),
        $this->escape($value)
    );
}