Backdoor is a software program that gives an attacker unauthorized access to a machine and the means for remotely controlling the machine without the user's knowledge.

后门是一个软件程序，使黑客未经授权访问的机器和手段，远程控制的机器在用户不知道。

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Companies that fail to implement an effective cross-selling program actually do a disservice to their customers and in effect, leave the backdoor open to their competitors.

不能实施有效的交叉销售项目的公司实际上危害了他们的顾客，并且对他们的竞争者打开了的后门。

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Once launched, the virus is designed to install a Trojan horse or backdoor program, and allow investigators to record everything typed into that machine, thereby getting around encryption and passwords.

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The backdoor could take the form of an installed program or subvert the system through what is known as a rootkit, a malicious software hard to detect.

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