Zero-day attack Computer threats that prey on software weaknesses developers had not identified.

是指电脑被攻击是因为电脑软件上有开发者没有发现的缺陷，从而被黑客利用；

youdao

The malware that led to the hacking of security giant RSA may have been a "zero-day attack" – ie, it had never been seen before – but the method of infection was nothing new.

恶意软件导致安全巨人RSA公司遭到“zero-day attack”攻击（指系统有缺陷，被黑客抓住而发起的攻击）--通过IE，以前没有发生过这种事--但是攻击的技术却是老套。

youdao

In turn the current exploiting of the flaw is known as a "zero-day" attack.

所以说，现在利用这一漏洞进行的攻击被称为“零日”攻击。

youdao

When it first hit, it was a "zero-day attack, " in hacker parlance.

FORBES: Criminal Outbreak

Hackers infected banner ads run by marketing firms such as Germany's Falk Esolutions, causing users who visited certain Web sites displaying Falk ads to download a Trojan horse that steals credit card numbers by exploiting yet another undetected vulnerability in Microsoft's Internet Explorer (a zero-day attack, once again).

FORBES: Criminal Outbreak