They supply a simple layer on top of what the underlying system provides.

它们在基础系统所提供的安全性之上提供一个简单的安全层。

youdao

This scheme works well for aspects that require very little knowledge of the underlying system.

对于需要很少底层系统信息的方面，这个方案可以工作得很好。

youdao

Components described below such as widget sets and desktop environments, use X as the underlying system.

下面介绍的组件，例如部件集和桌面环境，使用X作为底层的系统。

youdao

So we've got to reform the underlying system.

WHITEHOUSE: THE WHITE HOUSE

All Android users eventually will have access to the application, Mr. Zuckerberg said, without the need to modify their underlying operating system.

WSJ: Facebook Shows Off New Home App for Android Smartphones

This gives the attacker the ability to bypass anti-exploitation technologies in the underlying operating system and exploit flaws in the OS that otherwise would not be exploitable.

FORBES: How Bad Assumptions Are Making Software Less Secure