您的计算机如何感染病毒、木马、工作或间谍软件？恶意软件可以通过哪些方式感染您的Windows计算机？哪些类型的文件带有病毒和恶意软件？我们将简要介绍这些问题，并查看一些文件，看看它们是否会感染您的计算机或手机。
(Malware)众所周知，Malware （恶意软件）是旨在破坏用户计算机、服务器或网络的软件；或通过窃取个人或其他敏感信息、通过各种诈骗和其他邪恶业务来欺骗用户，从而对计算机用户造成伤害。蠕虫(Worms)、特洛伊木马、病毒和流氓安全软件是一些最流行的恶意软件类型。
恶意软件(Malware)始于 1980 年代，其程序包括 1986 年的Brain boot-sector 病毒和 1988 年在 Internet 上传播的Morris蠕虫。这些病毒的设计主要是为了给用户造成严重破坏。使用受感染计算机的人可能会看到模拟消息或奇怪的视觉效果。
编写早期恶意软件的人在黑客的地下世界中寻求声名和尊重，这些黑客在严密保护的病毒交换 (VX) 论坛中相互联系，并吹嘘他们造成的破坏。
今天，职业犯罪分子已经取代了业余病毒作者。VX 论坛已经发展成为广泛的在线黑市，提供全面的产品和服务选择。其中许多产品和服务都与僵尸网络相关，可用于分发和安装其他恶意软件。
网络上看似无限的信息、图像和机会的吸引力可能会让我们忘记这种访问会给我们的计算机带来风险。网络犯罪分子不遗余力地在您的计算机上安装病毒和间谍软件等恶意软件（malware），以试图破坏或控制它，使用您的电子邮件或即时消息 (IM) 将恶意软件传播到朋友的计算机，或监视您的在线活动，最终企图窃取敏感的个人信息和金钱。
犯罪分子使用两种广泛的策略来试图突破计算机的防御：
- 他们通过利用其软件中的意外漏洞或闯入由弱密码保护的帐户来在计算机上安装恶意软件。
- 他们试图诱骗您安装他们的恶意软件。他们可以通过您认为是图片或电影的下载内容，或者您在电子邮件或即时消息 (IM) 中单击的链接或社交网络上的链接来提供它。或者他们可能会试图恐吓您单击他们的按钮或链接，并带有虚假警告您的计算机有病毒。
你怎么会感染电脑病毒
Windows 计算机感染病毒或恶意软件的常见方式有：
- 你下载盗版软件
- 您从恶意网站下载并安装软件
- 您从官方应用商店下载并安装已被入侵的应用
- 您在未阅读EULA或取消选中第三方软件提供的情况下安装Bundleware ，以(Bundleware)避免安装 PUP(avoid installing PUPs)
- 您单击的链接会将您带到恶意或受感染的网站，这些网站会自动将恶意代码下载到您的 PC
- 您盲目地单击您倾向于信任的朋友的社交媒体链接，从而将恶意软件下载到您的计算机或移动设备
- 您单击恶意电子邮件附件而不检查发件人是谁
- 您打开来自其他系统的受感染Office文件(Office)
- 你点击恶意广告——Malvertising——嵌入了隐藏代码
- 您将受感染的USB 连接(USB)到您的计算机并使用它，而无需对其进行恶意软件扫描。
最常用的文件类型作为恶意软件的载体
可执行文件或.exe 文件(.exe files)可能很危险，因此即使您的电子邮件客户端也不会从电子邮件中下载此类文件。EXE、COM、MSI等是您需要非常小心的三种类型 - 无论是在电子邮件中出现还是从任何网站下载。在打开它们之前，请务必使用反恶意软件扫描所有附件和下载。
PDF会携带病毒吗？您可以从PDF中获取病毒吗？
不仅携带恶意软件，PDF还可以执行网络钓鱼(Phishing)的功能。可移植文档格式(Document Format)( PDF ) 文件包含可能感染您的计算机的活动元素。动态元素和Javascript的存在使它们变得危险。但这在很大程度上取决于解析文件的PDF阅读器。(PDF)
如果它负责打开、读取、编辑和关闭文件的所有方面，那么被感染的机会就会减少。您使用的PDF阅读器应该能够检测堆栈溢出并扫描PDF文件中的链接。
谈到链接，钓鱼者通常会在PDF文件中包含一个或多个重定向URL 。(URLs)无辜的读者相信链接并点击它，从而丢失他们的数据。解决此问题的一种方法是将链接直接复制粘贴到浏览器地址栏中，以便浏览器中内置的URL扫描程序可以查看该链接是否是恶意的。(URL)并非所有浏览器都可能具有此类功能，但Internet Explorer(Internet Explorer)、Edge、Chrome、Firefox等主流浏览器确实具有这些功能。您也可以使用URL扫描器作为浏览器的附加组件。
因此，总而言之，确保您可以从PDF中感染病毒，并且您也可能被误导，使用重定向链接或文件中的缩短链接与恶意网站/人员共享您的信息。
您可以从图像文件中获取病毒吗？
一个简单的BMP图像文件能做什么？好吧(Well)，它可以包含一些二进制代码，当您打开它并感染您的计算机时，这些代码可能会执行。看似无辜的图像文件是攻击和传播病毒的万无一失的方法。我们中有多少人在从Internet下载图像后真正运行恶意软件扫描程序？
用户认为它只是一个图像……而且图像不会造成伤害。因此，他们打开下载的图像而不采取任何预防措施，或者在电子邮件客户端中使用预览器查看它。在这两种情况下，计算机RAM的一部分都会保存要在屏幕上显示的数据。当您查看图像时，可执行的二进制代码会传播到您的计算机，从而感染它。
您可以从图像文件中获取病毒，就像从来自Internet的任何其他文件类型（包括电子邮件）中获取病毒一样。可以感染JPG、BMP、PNG等图像文件。它可能是Payload或Exploit。但只要图像没有被其他程序打开、执行或处理，病毒就不会被执行。
通过将可执行的 .exe 文件命名为 niceimage .jpg(.jpg) .exe ，也可以使其看起来像图像文件。由于默认情况下 Windows 隐藏文件扩展名，用户只看到.jpg部分并点击它认为它是一个图像文件。
供您参考，W32/Perrun是第一个报告的JPEG病毒。它从JPEG(JPEG)文件中提取数据，然后将受感染的数字图像注入图片文件。
Office 文档会携带病毒吗？
Office文档还可以作为恶意软件的良好载体。您可能已经看到附加了文档文件的电子邮件，并且电子邮件说明附件中存在更多详细信息。由于docx、doc、docm 和类似格式的Office文档允许活动元素，因此您可能会被感染。(Office)大多数恶意软件是通过文档中的宏下载的。这就是为什么除非您提出要求，否则Word不会在编辑模式下打开来自 Internet 的文件。
如果经过编程，Office 文档会携带宏病毒。脚本和宏使它变得容易。在大多数情况下，首先，宏会在稍后下载有效负载时运行以感染您的计算机——以避免被反恶意软件检测到。
阅读(Read)：如何使用在线 URL 扫描程序检查网站或 URL 是否安全(check if a Website or URL is safe using Online URL Scanners)。
观看YouTube会感染病毒吗？
这取决于您如何使用该网站。YouTube视频本身并不危险。但是，YouTube的一些方面是不受其控制的——恶意广告(malvertising)和视频内节目。拥有大量订阅者的用户可以使用视频节目。(Video)这减少了被感染的范围。但是，如果您单击覆盖在主要视频上的那些视频，可能会很危险。
广告也是如此。它们是活动元素，因此您的计算机很容易受到攻击，除非您特别注意不要点击广告。因此，答案是YouTube视频并不危险，只要您在与覆盖在主视频上的活动内容进行交互时要小心。从YouTube(YouTube)获取病毒的范围很小，但它仍然存在 - 任何其他网站都一样！
您会从Tumblr、Facebook或其他社交网站感染病毒吗？
这又取决于您要做什么。如果您只是上传文件而不单击任何链接，那么您是安全的。针对内容的广告(Ads)可能是恶意的。链接可以是尝试网络钓鱼的URL(URLs)。如果您下载图像并打开它而不扫描恶意软件，它会变得很危险。Windows SmartScreen通常可以很好地保护用户免受基于 Web 的威胁。
简而言之，社交工程恶意软件有可能潜伏在互联网(Internet)上的任何地方。你需要保持警惕。通过.exe(.exe)文件传播病毒的日子已经一去不复返了；现在它们可以携带任何文件扩展名，甚至可以嵌入到图像文件中。
结论(Conclusion)
因此，您会看到需要采取的最重要的预防措施，即仅从其官方来源下载受信任的软件，在安装过程中要非常小心并选择退出第三方产品，扫描您连接到设备的任何USB或驱动器，(USB)在单击任何 Web 链接之前(careful before you click on any web links)要非常小心，并在下载电子邮件附件之前采取预防措施(take precautions before downloading email attachments)。
现在阅读：(Now read:)
- 怎么判断你的电脑有没有病毒(How do you tell if your computer has a virus)
- 保护 Windows PC 的提示。(Tips to secure Windows PC.)
您可能还想了解恶意软件的演变以及这一切是如何开始的！
How can you get a computer virus, trojan, work, spyware or malware?
How can your computer get a virus, trojan, work or spyware? What are the ways malware can infеct yоur Windows computer? What types of files carry viruses and malware? We wіll touch upon these queѕtions in brief and take a lоok аt somе files and see if they сan infect your computer or phone.
Malware (malicious software), as we all know, is software that has been designed to damage a user’s computer, a server, or a network; or to cause harm to computer users by stealing personal or otherwise sensitive information, defrauding the user through various scams, and other nefarious business. Worms, trojan horses, viruses, and rogue security software are some of the most prevalent types of malware.
Malware began in the 1980s with programs like the Brain boot-sector virus in 1986 and the Internet-distributed Morris worm in 1988. These viruses were designed mostly to create havoc for users. People who used infected computers might see mocking messages or strange visual effects.
People who wrote early malware sought notoriety and respect in an underground world of hackers who connected with one another in closely guarded virus exchange (VX) forums and boasted about the havoc they created.
Today, professional criminals have displaced amateur virus writers. The VX forums have evolved into extensive online black markets that offer a comprehensive selection of products and services. Many of these products and services are related to botnets, which can be used to distribute and install other malware.
The appeal of the seemingly limitless information, images, and opportunities on the web can lead us to forget that this access comes with risk to our computers. Cybercriminals work relentlessly to install malicious software (malware) like viruses and spyware on your computer to try to damage or seize control of it, use your email or instant messages (IM) to spread malware to friends’ computers, or spy on your online activities, ultimately in an attempt to steal sensitive personal information and money.
Criminals use two broad strategies to try to break through a computer’s defenses:
- They install malware on a computer by exploiting unintended vulnerabilities in its software or by breaking into accounts guarded by weak passwords.
- They try to trick you into installing their malware. They can deliver it in downloads that you think are pictures or movies, or in links that you click in email or instant messages (IM), or on a social network. Or they may try to scare you into clicking their button or link with fake warnings that your computer has a virus.
How can you get a computer virus
The common ways your Windows computer can get infected with a virus or malware are:
- You download pirated software
- You download and install software from malicious websites
- You download and install already compromised apps from official app stores
- You install Bundleware without reading the EULA or unchecking the third-party software offers, so as to avoid installing PUPs
- You click on links which take you to malicious or compromised websites, which in turn download malicious code to your PC automatically
- You blindly click on social media links from friends, which you tend to trust, that initiates the download of malware to your computer or mobile device
- You click on malicious email attachments without checking who the sender is
- You open infected Office files which have come from another system
- You click on malicious advertisements – Malvertising – which has hidden code embedded
- You connect an infected USB to your computer and using it without scanning it for malware.
Most used file type as a carrier for malware
Executables or .exe files can be dangerous, and so even your email client won’t download such files from emails. EXE, COM, MSI, etc. are three types that you need to be very careful about – whether present in email or downloading from any website. Always scan all attachments and downloads with antimalware before opening them.
Do PDF carry virus? Can you get a virus from PDF?
Not just carry malware, but a PDF can also perform the function of Phishing. Portable Document Format (PDF) files contain active elements that can infect your computer. Dynamic elements and Javascript presence make them dangerous. But it largely depends on your PDF reader that parses the file.
If it takes care of all aspects of opening, reading, editing, and closing of the files, the chances of getting infected are less. The PDF reader you use should be able to detect stack overflow and scan links inside the PDF file.
Talking of links, it is common for phishers to include one or more redirect URLs in PDF files. Innocent readers believe the link and click on it thereby losing their data. One way to get around this is to copy-paste links directly into the browser address bar so that the URL scanners built into the browser can see if the link is malicious. Not all browsers may have such functions but the mainstream ones like Internet Explorer, Edge, Chrome, Firefox do have them. You may also use URL scanners as add-ons for your browser.
So in conclusion, sure you can get a virus from a PDF, and you can also be misled into sharing your information with malicious sites/people using redirect links or shortened links in the file.
Can you get a virus from image files?
What can a simple BMP image file do? Well, it can contain a few bits of binary code that may execute when you open it and infect your computer. Seemingly innocent-looking image files are a foolproof way to strike and spread the virus. How many of us really run malware scanner after downloading images from the Internet?
Users think it is just an image… and that images cannot harm. So they open downloaded images without taking any precautions or view it in the email client with a previewer. In both cases, a portion of the computers RAM keeps data to be shown on screen. As you are viewing the image, the executable binary code spreads to your computer, thereby infecting it.
You can get a virus from image files as you would from any other file types originating from the Internet (email included). An image file like JPG, BMP, PNG, etc can be infected. It could be a Payload or an Exploit. But the virus will not be executed as long as the image is not opened, executed, or processed by another program.
An executable .exe file can also be made to appear like an image file by naming it niceimage.jpg.exe. Since Windows by default hides file extensions, users see only the .jpg part and click on it thinking it’s an image file.
For your information, W32/Perrun was the first reported JPEG virus. It extracted data from JPEG files and then injected picture files with infected digital images.
Can Office Documents carry a virus?
Office documents also serve as a good carrier for malware. You might have seen emails where document files are attached, and the email says more details present in the attachment. Since Office documents like docx, doc, docm and similar formats allow active elements, you may be infected. Most of the malware is downloaded by macros present in the documents. That is why Word will not open an internet originating file in edit mode unless you ask it.
Office documents carry Macro Virus if programmed to do so. Scripts and macros make it easy. In most cases, first, the macro runs to infect your computer while the payload is downloaded later – to avoid detection by antimalware.
Read: How to check if a Website or URL is safe using Online URL Scanners.
Can you get a virus by watching YouTube?
It depends on how you use the site. YouTube videos as such are not dangerous. But then, few aspects of YouTube are beyond its control – malvertising and in-video programming. Video programming is available to users who have a good number of subscribers. That reduces the scope of being infected. But it may be dangerous if you click on those videos overlaying on the main videos.
It is the same with advertisements. They are active elements, so your computer is vulnerable unless you make it a point not to click advertisements. So the answer is that YouTube videos are not dangerous as long as you take care while interacting with the active content overlaying the main video. The scope of acquiring a virus from YouTube is low, but still, it is there – and it is the same for any other website for that matter!
Can you get a virus from Tumblr, Facebook, or other social sites?
It again depends on what you are trying to do. If you are simply uploading files and not clicking any links, you are safe. Ads against content could be malicious. Links can be URLs that try phishing. If you download an image and open it without scanning for malware, it gets dangerous. The Windows SmartScreen usually does a good job of protecting users from web-based threats.
In short, there is the possibility of socially engineered malware lurking everywhere on the Internet. You need to be on guard. Gone are the days when a virus was delivered via .exe files; now they can carry any file extension and can even be embedded in image files.
Conclusion
So you see the most important precautions you need to take, is to download only trusted software from their official sources, be very careful during its installation and opt-out of 3rd party offers, scan any USB or drive which you connect to your device, be very careful before you click on any web links and take precautions before downloading email attachments.
Now read:
- How do you tell if your computer has a virus
- Tips to secure Windows PC.
You might want to also read about the evolution of malware and how it all began!
