Questions tagged [malware]

Malware is any software application which subverts the will of the legitimate owner of a computer, by means of force or subterfuge, with or without personal or monetary gain on the part of the creator.

"Malware" is a portmanteau of "malicious" and "software"

Common forms of malware include:

  • Botnet clients, which grant the malware author some degree of control over the compromised operating system and are generally employed in sending spam e-mail and may be rented out to perform DDoS attacks.
  • Data exfiltrators/Spyware, which collect and transmit data about the computer they reside on back to the creator. These are commonly used to target login and account details for financial, social networking, and gaming websites.
  • Rogue Utility Applications, which attempt to use scare tactics in order to entice the computer's user to purchase the "full version" of the Rogue Utility.
  • Adware, which causes advertisements to appear on the user's desktop, in web pages, or elsewhere.
  • Rootkits, which attempt to conceal the presence of both the rootkit and (usually) an accompanying piece of malware from another category from standard system tools and diagnostic utilities.
  • Ransomware, which encrypts the target's data and demands payment to return access of the data to the owner.

Useful Resources:

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How is the "WannaCry" Malware spreading and how should users defend themselves from it?

There's a new strain of attacks which is affecting a lot of systems around the world (including the NHS in the UK and Telefonica in Spain) which is being called "WannaCry" amongst other names. It seems to be a both a standard phishing/ransomware…
Rory McCune
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What should you do if you catch encryption ransomware mid-operation?

You boot up your computer one day and while using it you notice that your drive is unusually busy. You check the System Monitor and notice that an unknown process is using the CPU and both reading and writing a lot to the drive. You immediately do a…
Fiksdal
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Search for military installed backdoors on laptop

My laptop was confiscated by the military institute of my country and they made me to give them all my passwords (I cannot tell you the name of my country). They did not give it back to me for one week (yes, it was out of my sight for a while). I…
Posse
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Help! My home PC has been infected by a virus! What do I do now?

This is an attempt to ask a canonical question as discussed in this old meta post. The goal is to create something helpful that can be used as a duplicate when non experts ask about virus infections. Let's say that I have determined beyond doubt…
Anders
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How secure are virtual machines really? False sense of security?

I was reading this CompTIA Security+ SYO-201 book, and the author David Prowse claims that: Whichever VM you select, the VM cannot cross the software boundaries set in place. For example, a virus might infect a computer when executed and spread…
T. Webster
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How do you explain the necessity of "nuke it from orbit" to management and users?

When a machine has been infected with malware, most of us here immediately identify the appropriate action as "nuke it from orbit" - i.e. wipe the system and start over. Unfortunately, this is often costly for a company, especially if backups are…
Polynomial
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How can USB sticks be dangerous?

We all know the story of the USB drive left outside a power plant which was found by a worker and inserted into a computer to see the contents which then allowed a hack to ensue. Here is my question, how? I get that code is executed but how? I would…
TheHidden
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What is the safest way to deal with loads of incoming PDF files, some of which could potentially be malicious?

As an investigative journalist I receive each day dozens of messages, many of which contain PDF documents. But I'm worried about some of the potentially malicious consequences of blindly opening them and getting my computer compromised. In the past,…
Tom the journalist
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Has it been mathematically proven that antivirus can't detect all viruses?

What analysis was Bruce Schneier referencing when he wrote: Viruses have no “cure.” It’s been mathematically proven that it is always possible to write a virus that any existing antivirus program can’t stop. From the book Secrets & Lies by Bruce…
Cate
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Is there any way to safely examine the contents of a USB memory stick?

Suppose I found a USB memory stick lying around, and wanted to examine its contents in an attempt to locate its rightful owner. Considering that USB sticks might actually be something altogether more malicious than a mass storage device, is there…
200_success
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Alternatives to anti-virus for keeping oneself safe

I have read a lot of articles that talk about how using an AV is less safe than not having one for more intermediate PC users who are careful with what they click and download. For example, here are a couple of articles:…
delacroix
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Can a virus destroy the BIOS of a modern computer?

In the late 1990s, a computer virus known as CIH began infecting some computers. Its payload, when triggered, overwrote system information and destroyed the computer's BIOS, essentially bricking whatever computer it infected. Could a virus that…
user73910
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Should I get an antivirus for Ubuntu?

Considering the recent thread regarding anti-virus for the Mac I wonder how many of the arguments put forth are relevant today to Linux systems, specifically Ubuntu. There are no known Ubuntu desktop malware in the wild. GNU/Linux is a very…
dotancohen
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Can a malware power on a computer?

I've just downloaded and executed a piece of malware on my computer. I don't have much time right now, so I just powered it off (turned it off via the Start menu), hoping that it won't be able to steal any data or do malicious activities until I can…
Benoit Esnard
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What is the risk of copy and pasting Linux commands from a website? How can some commands be invisible?

Like all beginners in the land of Linux, I usually look for websites that contain some useful shell commands, mark it with my mouse, copy it (CTRL + C) and paste it into a terminal. For example, if I need to install package_name.deb sudo apt-get…
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