IT Security Stack Exchange
IT Security Stack Exchange

Questions tagged [virus]

A computer virus is a program or piece of code that tends to be malicious and is loaded onto your computer without your knowledge and runs against your wishes.

A computer virus is a program or piece of code that tends to be malicious and is loaded onto your computer without your knowledge and runs against your wishes.

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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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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 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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Can a computer virus be stored somewhere else than on the hard drive?

Are there viruses that have managed to hide themselves somewhere other than on the hard drive? Like CPU cache or on the motherboard? Is it even possible? Say I get a virus, so I get rid of the HDD and install a new one. Could the virus still be on…
Ivan Bilan
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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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How are anti viruses so fast?

The common anti-virus (to my knowledge) uses a kind of brute force type method where they get the hash of the file and compare it to thousands of known virus' hash. Is it just they have servers with super fast SSD and they upload the hashes to that…
Harry
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Can a rogue .wmv file "hijack" Windows Media Player?

I've downloaded a .wmv file using P2P. Attempting to play it with Media Player Classic (K-Lite Codec Pack) only gave me a green square in the playback window: I noticed that the video came with a readme file, however; I found the following…
user4520
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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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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…
GAD3R
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Can my mouse have virus and infect other machines?

This is my mouse. I used it with my old computer which was full of viruses. If I use this mouse for my new PC, can my new computer be infected from my mouse?
Nhật Phát
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Why is so much ransomware breakable?

The site: https://www.nomoreransom.org/ offers many decrypter tools for ransomware. But why? It shouldn't be so hard to use the Windows Crypto API (e.g. just google "create AES Key in Windows") to create AES Keys, encrypt them with a locally…
kiara
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Can malware be attached to an image?

I have a small number of employees who use a company computer but these people aren't very tech-savvy. They use an email client and a messaging client. I'm pretty sure they wouldn't click on a .exe or .zip file in an email without thinking, and I…
user2143356
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