Humail & Zero-Day
This article explains why using HUMail technology is recommended in the case of messages from ZeroZero-Day.
When there is no patch yet available to mitigate the vulnerability being exploited.
Zero days are sometimes used in Trojans, rootkits, viruses, worms and other types of malware to help them spread and infect other computers. Also spelt "zeroday", "0day" and "0-day".
When HUMail is activated for the domain or a filtering group, it holds back any message (relayed by our gateways) that may contain a virus (infected attachment) that has not yet been detected by the antivirus engines.
Humail's ability to retain the message means that antivirus systems can be updated in the meantime.
In this way, if the user tries to release the message containing an infected item, it will be detected as a virus and will never be delivered.