后门这个名字可能听起来很奇怪，但如果它位于您的计算机系统(computer system)或网络上，它可能会非常危险。问题是，后门有多危险，如果您的网络受到影响，会有什么影响。
在这篇面向初学者的文章中，我们将了解什么是后门以及黑客如何使用后门来访问世界各地的计算机系统。
什么是后门
好的，所以后门基本上是黑客绕过计算机上常规加密方法的一种方式，然后允许他们进入系统并收集密码和其他重要信息等数据。有时后门是为所谓的良好目的而设计的。例如，当系统管理员失去访问权限时，可能会出现这种情况，因此，只有后门可以提供访问权限。
在许多情况下，受害者不知道他们的计算机上安装了后门，这是一个问题，因为他们不知道他们的数据被外人窃取并可能在暗网上出售。让我们详细谈谈这个话题。
- 后门的历史与例子
- 黑客如何利用后门
- 后门是如何出现在计算机上的？
- 开发者安装后门
- 黑客创建的后门
- 发现后门
- 如何保护计算机免受后门攻击。
您可以在这里阅读病毒、木马、蠕虫、广告软件、Rootkit等之间的区别。
1] 后门的历史和例子
后门已经存在了很长时间，但它们主要是由创建者设置的后门。例如，美国国家安全局(NSA)早在 1993 年就开发了一种用于计算机和电话的加密芯片。这款芯片的有趣之处在于它附带的内置后门。
从理论上讲，该芯片旨在保护敏感信息的安全，但同时允许执法部门监听语音和数据传输。
令人惊讶的是，后门的另一个例子将我们引向了Sony。你看，这家日本公司早在 2005 年就向全球客户运送了数百万张音乐 CD，但这些产品存在巨大问题。该公司选择在每张 CD 上安装一个 rootkit，这意味着，只要将 CD 放入计算机，rootkit 就会自行安装到操作系统上。
完成后，rootkit 将监控用户的收听习惯并将数据发送回索尼(Sony)服务器。不用说，这是 2005 年最大的丑闻之一，直到今天它仍然笼罩在索尼(Sonys)的头上。
阅读(Read)：恶意软件的演变——这一切是如何开始的！
2] 黑客如何利用后门
发现数字后门并不容易，因为它与物理后门不同。在某些情况下，黑客可能会使用后门对计算机或网络造成损害，但在大多数情况下，这些东西是用来复制文件和进行间谍活动的。
从事间谍活动的人往往会查看敏感信息，他们可以做到这一点而不留痕迹。这是一个比复制文件更好的选择，因为该路径通常会留下一些东西。但是，如果做得好，复制信息不会留下痕迹，但很难完成，因此，只有最先进的黑客才能接受这一挑战。
当归结为造成破坏时，黑客将决定只向系统发送恶意软件，而不是执行秘密任务。这是最简单的选项，它需要速度，因为检测不需要很长时间，尤其是在系统高度安全的情况下。
阅读(Read)：勒索软件攻击、定义、示例、保护、删除、常见问题解答(Ransomware Attacks, Definition, Examples, Protection, Removal, FAQ)。
3]计算机上的后门是如何产生的？(How)
根据我们的研究，后门出现在计算机上的主要方式有三种。它们通常由开发人员创建、由黑客创建或被发现。让我们更多地谈谈这些。
4] 开发者安装后门
计算机或计算机网络(computer network)上最危险的后门之一是开发人员安装的后门。在某些情况下，应用程序开发人员会在产品中放置后门，以便在需要时随时使用。
如果他们想让执法部门进入，监视公民，如果产品被竞争对手出售，以及其他原因，他们就会这样做。
阅读(Read)：您如何判断您的计算机是否有病毒(How do you tell if your computer has a virus)？
5]黑客创建的后门
在某些情况下，黑客无法在系统上找到后门，因此，最好的办法是从头开始创建一个。为了完成它，黑客需要创建一条从他们的系统到受害者系统的隧道。
如果他们没有手动访问权限，黑客必须欺骗受害者安装一个允许他们从远程位置访问计算机的专用工具。从那里，黑客可以轻松访问重要数据并相对轻松地下载它们。
6]黑客发现后门
在某些情况下，黑客不需要创建自己的后门，因为由于开发人员的不良做法，系统可能有所有相关人员都不知道的后门。黑客，如果幸运的话，可能会遇到这个错误并充分利用它。
从我们多年来收集的信息来看，后门往往出现在远程访问软件中，这是因为这些工具旨在让人们从远程位置访问计算机系统。
7]如何(How)保护计算机免受后门攻击
保护您的计算机免受内置后门的侵害并不容易，因为一开始就很难识别它们。然而，当涉及到其他类型的后门时，有办法让事情得到控制。
- 监控计算机上的网络活动(Monitor network activity on your computer(s))：我们相信监控 Windows 10 计算机上的网络安全是保护您的系统免受潜在后门攻击的最佳方法之一。利用Windows 防火墙(Windows Firewall)工具和其他第三方网络监控程序。
- 每 90 天更改一次密码(Change your password every 90 days)：通过多种方式，您的密码是您计算机上所有敏感信息的门户。如果你有一个弱密码，那么你马上就创建了一个后门。如果您的密码太旧（例如，多年前），情况也是如此。
- 下载免费应用时要小心(Careful when downloading free apps)：对于那些使用Windows 10的用户来说，Microsoft Store可能是下载应用程序最安全的地方，但用户使用的大多数程序都缺少Microsoft Store 。这种情况迫使用户继续在网络上下载应用程序，这就是事情可能出错的地方。我们建议在使用Microsoft Defender(Microsoft Defender)或任何您喜欢的防病毒和恶意软件工具安装之前扫描每个程序。
- 始终使用安全解决方案(Always use a security solution)：每台由Windows 10提供支持的计算机都应安装并使用安全软件。默认情况下，Microsoft Defender应该在每台设备上运行，因此开箱即用，用户受到保护。但是，用户可以使用许多选项，因此请使用最适合您需求的选项。
勒索软件(Ransomware)、流氓软件(Rogue software)、Rootkits、僵尸网络、RATs、恶意广告(Malvertising)、网络钓鱼(Phishing)、下载驱动攻击(Drive-by-download attacks)、在线身份盗窃(Online Identity Theft)，现在都在这里。现在需要采取一种综合方法来对抗恶意软件，因此防火墙(Firewalls)、启发式(Heuristics)等也成为了武器库的一部分。有许多免费的防病毒软件(free antivirus software)和免费的Internet 安全套件(Internet Security Suites)，它们的作用与付费选项一样好。您可以在此处阅读更多信息 -保护 Windows 10 PC 的提示。(Tips to secure Windows 10 PC.)
What is a Backdoor attack? Meaning, Examples, Definitions
The name backdoor might sound strange, but it can be very dangerous if one is located on your computer system or network. The question is, how dangerous is a backdoor, and what are the implications if your network is affected.
In this article meant for beginners, we are going to take a look at what a backdoor is and how hackers use backdoors to gain access to computer systems around the world.
What is a Backdoor
OK, so a backdoor is basically a way for hackers to bypass regular encryption methods on a computer, which then allows them to enter the system and collect data such as passwords and other important information. Sometimes a backdoor is designed for so-called good purposes. For example, a situation may arise when a system admin loses access, and as such, only a backdoor could provide access.
In many cases, victims have no idea a backdoor is installed on their computer, and that’s a problem because they have no idea their data is being siphoned by outsiders and probably sold on the dark web. Let us talk about this topic in detail.
- The history of backdoors with examples
- How hackers take advantage of backdoors
- How backdoors come about on a computer?
- Developer installed backdoor
- Backdoor created by hackers
- Discovered backdoors
- How to protect computers against backdoors.
You can read the difference between Virus, Trojan, Worm, Adware, Rootkit, etc, here.
1] The history of backdoors with examples
Backdoors have been around for quite a long time now, but they were primarily backdoors put into place by the creators. For example, the NSA back in 1993 developed an encryption chip for use in both computers and phones. What was interesting about this chip is the built-in backdoor that came with it.
In theory, this chip was designed to keep sensitive information secured, but at the same time allow law enforcement to listen in on voice and data transmissions.
Another example of a backdoor leads us to Sony, surprisingly. You see, the Japanese company back in 2005 shipped millions of music CDs to customers around the world, but there was a huge problem with these products. The company chose to install a rootkit on each CD, which means, whenever the CD is placed in a computer, the rootkit then installs itself onto the operating system.
When that is done, the rootkit will monitor the user’s listening habits and send the data back to Sony servers. Needless to say, it was one of the biggest scandals of 2005, and it still hangs over Sonys head to this very day.
Read: Evolution of Malware – How it all began!
2] How hackers take advantage of backdoors
It’s not easy to spot a digital backdoor since it is not the same as a physical backdoor. In some cases, hackers might use a backdoor to cause damage to a computer or network, but in most situations, these things are used to copy files and to spy.
A person spying tends to look at sensitive information, and they can do this without leaving a trace. It is a much better option than copying files since that route usually leaves something behind. However, when done right, copying information does not leave traces behind, but it is difficult to accomplish, therefore, only the most advanced of hackers take on this challenge.
When it comes down to causing havoc, a hacker will decide to just deliver malware to the system rather than go about on a covert mission. This is the easiest option, which requires speed because detection does not take very long, especially if the system is highly secured.
Read: Ransomware Attacks, Definition, Examples, Protection, Removal, FAQ.
3] How backdoors come about on a computer?
From our research, there are three primary ways for a backdoor to appear on a computer. They are usually created by developers, created by hackers, or discovered. Let us talk more about those.
4] Developer installed backdoor
One of the most dangerous backdoors on a computer or computer network is the one installed by the developer. In some cases, application developers place backdoors in a product that they can use whenever the need arises.
They do it if they want to give law enforcement access, spy on citizens, if the product is being sold by a rival, among other reasons.
Read: How do you tell if your computer has a virus?
5] Backdoor created by hackers
In some cases, a hacker is unable to find a backdoor on a system, therefore, the next best thing is to create one from scratch. To get it done, the hacker is required to create a tunnel from their system to that of the victim.
If they do not have manual access, the hackers must trick the victim into installing a specialized tool that allows them to access the computer from a remote location. From there, hackers can easily access important data and download them with relative ease.
6] Backdoor discovered by hackers
In some situations, there is no need for hackers to create their own backdoors because due to bad developer practice, a system might have backdoors unknown to all involved. Hackers, if they’re lucky, might come across this error and take full advantage of it.
From what we’ve gathered over the years, backdoors tend to show up in remote access software than anything else, and that is because these tools were designed to give folks access to a computer system from a remote location.
7] How to protect computers against backdoors
It’s not easy to protect your computer from built-in backdoors because it is difficult to identify them in the first place. However, when it comes down to other types of backdoors, there are ways to get things under control.
- Monitor network activity on your computer(s): We believe that monitoring network security on your Windows 10 computer is one of the best ways to protect your system from potential backdoors. Take advantage of the Windows Firewall tool, and other third-party network monitoring programs.
- Change your password every 90 days: In more ways than one, your password is the gateway to all sensitive information on your computer. If you have a weak password, then right away you’ve created a backdoor. The same goes if your password is too old, for example, multiple years old.
- Careful when downloading free apps: For those with Windows 10, the Microsoft Store is probably the safest place to download apps, but the Store is lacking in most programs used by users. This situation forces the user to continue downloading apps on the web, and this is where things can go very wrong. We suggest scanning each program before installing with Microsoft Defender or any of your favorite anti-virus and malware tool.
- Always use a security solution: Every computer that is powered by Windows 10 should have security software installed and in use. By default, Microsoft Defender should be running on every device, so right out of the box, the user is protected. However, there are many options available to the user, so make use of the one that works best for your needs.
Ransomware, Rogue software, Rootkits, Botnets, RATs, Malvertising, Phishing, Drive-by-download attacks, Online Identity Theft, are all here to stay now. One now needed to take an integrated approach to fight malware, and hence Firewalls, Heuristics, etc, were also made a part of the arsenal. There are many free antivirus software and free Internet Security Suites, that act as good as the paid options. You can read more here on – Tips to secure Windows 10 PC.
