The only known weaknesses Oberon has are iron (like the rest of his race), and energy.

A security exploit is a prepared application that takes advantage of a known weakness.

In fact, it was a very known weakness that I had.

One of their few known weaknesses is that they are reluctant to cross running water.

They have few known weaknesses, but one of these is that they are reluctant to cross running water.

It's time we made that clear: a known weakness.

They have few known weaknesses, one of which is that they do not like to cross running water.

There are only two known weaknesses of the control a Yeerk exerts over a human.

The only known weakness in War Angel seems to be psychological.

Among Myrddraal's known weaknesses is that they are reluctant to cross running water.