一个严重的程序漏洞导致我们整个网络崩溃。

A ___bug has crashed our entire network.

千年虫是一个著名的计算机问题。

The millennium ___bug was a famous computer problem.

在发布软件更新之前，我们需要修复这个漏洞。

We need to fix this ___bug before releasing the software update.