Antivirus or anti-virus software is used to prevent, detect, and remove malware, including but not limited to computer viruses, computer worm, trojan horses, spyware and adware.

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64
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10answers
5k views

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 ...
61
votes
15answers
3k views

How to write an email regarding IT Security that will be read, and not ignored by the end user?

I've observed that several of our users are ignoring messages sent from IT Security managers, and also the system generated "You just sent a virus" notifications. The problem seems to be among people ...
32
votes
8answers
4k views

Are two anti-virus better than one in protecting your computer?

A century old adage: The more the merrier. In general, does this adage hold true in regards to the number of anti-virus software you should have on your PC? Are there any limits before it actually ...
29
votes
2answers
2k views

How do antiviruses scan for thousands of malware signatures in a short time?

Most antiviruses have hundreds of thousands or even millions of malware signatures and yet they scan many files in a reasonable short time with high detection rates. Even real-time scanners doesn't ...
28
votes
2answers
6k views

How secure is the Windows 8 included Anti Virus known as Windows Defender?

How secure is the new Windows 8 anti virus known as Windows Defender? Does it have a protection against malware which uses UAC bypass/process injection/rootkits/process persistence/running the binary ...
21
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2answers
647 views

Cohen's problem

Fred Cohen determined theoritically that viral detetction is an undecidable problem. Can anyone provide an intuitive reasoning for that? Background Fred Cohen experimented with computer viruses ...
19
votes
6answers
14k views

How to scan a PDF for malware?

Can anyone suggest an automated tool to scan a PDF file to determine whether it might contain malware or other "bad stuff"? Or, alternatively, assigns a risk level to the PDF? I would prefer a free ...
19
votes
4answers
1k views

Are anti-virus companies companies regularly committing software piracy?

As Mikko Hypponen highlighted in a recent tweet, anti-Virus companies collect and store both samples of malicious software and samples of legitimate software: This got me to thinking, what ...
18
votes
2answers
3k views

How does a crypter for bypassing antivirus detection work?

I am talking about crypters used to encrypt files like viruses and keyloggers for the sole purpose of bypassing antivirus detection. How do they work?
18
votes
3answers
859 views

Are older viruses removed from virus definition files?

Antivirus software receives constant updates in the form of virus definition files, containing the patterns used to identify viruses. It is a feature present on most (if not all) major AV for at least ...
16
votes
5answers
909 views

Why would a virus writer bother to check to see if a machine is infected before infecting it?

I was looking at the tripartite structure of a virus, and it seems to check to see if a computer is infected before infecting it with the virus. Would this be an attempt to use files that are already ...
16
votes
6answers
577 views

How to deal with a person who gets easily fooled by internet and mail scams?

alternative title: How to deal with a person who has gotten paranoid and doesn't want to go online anymore? A person, who has over the years been scammed many times, by bad spam/fraud emails, and ...
15
votes
8answers
1k views

Are signature based antivirus or antimalware effective?

Are signature based antivirus or antimalware solutions effective? Has the battle been lost against the ever increasing amount of malware, particularly rootkits, that are in the wild?
13
votes
4answers
971 views

How is a worm different from a virus?

In spite of various online articles, I'm a bit unclear on the distinction between a "worm" and a "virus". Two related questions-- Is there a useful and clear distinction here or no? If so, what is ...
12
votes
4answers
5k views

Does a webserver need an antivirus software installed?

In what cases does a webserver need an antivirus software installed? When it is not required? If it is required sometimes, what should be considered when choosing the right one to install? (In my ...
11
votes
5answers
221 views

What are the areas to focus on to protect users and devices?

What are the areas or technologies to focus on to protect users and devices? Are patching, antivirus and firewalls still the main areas? How do you defend against attacks against vulnerabilities ...
11
votes
3answers
32k views

How serious is InstallIQ?

Background: Recently I've seen hits for InstallIQ a "potentially unwanted application" from ESET. From what I can find it seems like this is an installer wrapper that asks people to install other ...
10
votes
4answers
906 views

How effective are anti-virus products against real-world threats?

In a recent interview† with Dave Kennedy, he in passing pegged the average effectiveness of anti-virus products as detecting approximately 3% to 5% of current active threats. While AV comparisons ...
10
votes
1answer
1k views

How do anti-virus apps for Android work?

There seems to be a lot of anti-virus apps for Android. On a desktop or server an anti-virus must run with super-user privileges, however I am pretty sure these mobile anti-viruses are running as an ...
8
votes
6answers
1k views

Whats the probability of a personal computer being hacked?

For a normal computer user following these practices: Have an up to date anti-virus with a firewall installed (Norton). Do not install cracked software. Do not open suspicious links or download ...
7
votes
8answers
629 views

Battling Malware without spending money

Our environment consists of about 80 users running Windows 7. Previous to me showing up as a full time IT employee, the company had contracted an outsource IT solution. As part of their set up, they ...
7
votes
2answers
300 views

Are there any independent organizations doing (publicly available) IT security research?

When looking up security risks on the net I find that all research being cited (if any is cited) always seems to come from the Anti-Malware companies. (just e.g., this article cites F-secure, AVG and ...
7
votes
2answers
251 views

How do AV vendors choose malware names?

If you take a look at McAfee's recent malware page, you'll see that the names in the "Malware name" column aren't very human-readable: Downloader.a!cnz, W32/Autorun.worm.bgh, ...
7
votes
1answer
384 views

What steps do you take to keep both your computer and internet browsing secure?

I am thinking about your browser setup, antivirus protection, vpn, browsing best-practices and so on.
7
votes
1answer
714 views

Have any viruses leveraging the GPU been discovered in the wild? What is the mitigation?

This news article from 2010 discusses how a GPU can be used by a virus to avoid detection by common anti-malware/anti-virus software. The idea is to obfuscate the virus payload and leverage the GPU's ...
6
votes
4answers
523 views

How can Antivirus differentiate between a Trojan and a normal remote desktop application software?

RAT (Remote Access Tool, e.g. Sub7) are considered malicious by Antivirus software. How can it distinguish between such patches and a client application for commercial software like NetSupport ...
6
votes
2answers
789 views

Antivirus, antimalware and antispyware software. What is the difference?

What is the difference between antivirus, antimalware and antispyware software? If any clear distinction can be defined.
6
votes
2answers
306 views

Possible to detect packed executable?

A packer is a way of obfuscating an executable program, i.e., transforming so the result is still executable and has the same effect when run, but looks different (so it won't be detected by static ...
6
votes
3answers
317 views

Do any antivirus products use “canary files” to detect rootkits?

Recently, I've learned how some rootkits are able to hide certain files, services, etc. from programs in the kernel or user modes. This got me wondering: Are there any antivirus programs, or other ...
5
votes
5answers
4k views

Why Adobe is recommending McAfee security scan during flash player installation?

Why is Adobe recommending a McAfee security scan during the installation of flash player?
5
votes
4answers
443 views

How bad is a source code leak for an antivirus?

I was reading that Symantec suffered a source code leak and I was wondering how bad this is for a anti-virus product. Do these products rely heavily upon "(in)Security Through Obscurity" or does it ...
5
votes
2answers
1k views

Antivirus for scanning anonymous file uploads

Since I have no experience with AV solutions on Unix-like environments, I would need help with suggestions on something that can be suitable for scanning files that are uploaded by anonymous users ...
5
votes
1answer
329 views

How antivirus companies create virus defnitions for new outbreaks

This question quite amazes me. I dont understand how antivirus companies get info about the latest viruses. have they installed some kind of filters to monitor the internet traffic ? Or they are ...
5
votes
6answers
2k views

How can I tell whether this computer is part of a botnet?

One of the computers that I manage (in the family, not business) has a weird set of files in its boot: bash.exe, curl.exe, uname.exe, sed.exe, rm.exe, tail.exe, cut.exe, awk.exe, cat.exe, chmod.exe, ...
5
votes
3answers
383 views

How do anti-virus & anti-malware programs protect themselves?

I would assume that A/V products would need to employ the same kinds of techniques used by the software they are trying to cleanse to ensure that they can continue to run in such hostile environments. ...
5
votes
3answers
1k views

Are there faux/fake malicious websites to test web reputation services similar to EICAR?

Antivirus writers have agreed for their software to recognize a standard "fake" virus file - the EICAR file, to let users check, that the software is up and running. Are there any equivalent test ...
5
votes
1answer
255 views

AV boot disks and Truecrypt encrypted drives

I was wondering if there were any "how-to" guides on what is needed to modify AV boot disks, such as Sophos, kaspersky, AVG etc in order to load the decryption drivers/bootloader for Truecrypt before ...
4
votes
4answers
361 views

Is it worth it to get paid anti-virus software?

With the rise in cybercrime, I am slightly worried about my computer security. I have been using open sourced anti-virus AVG for years and it has been doing well. Are anti-virus software like Norton ...
4
votes
5answers
167 views

Should there be an anti-virus used on client provided files?

This is based on Stack Exchange podcast # 25. I really don't understand why there would need to be virus checking on uploaded files. It would generally be a bad idea to execute anything which was ...
4
votes
1answer
229 views

What is behaviourism and heuristic control in anti-virus software and how does it work?

In one local magazine I read interview with Adrian Porcescu, who is a technical consultant that works for Kaspersky Lab. Among other things, he says their anti-virus uses behaviourism and heuristic ...
4
votes
2answers
487 views

Can a firewall tamper with email attachments?

I am using Thunderbird as an email client for managing my different email accounts. Yesterday my friend sent me an email with a PDF attachment. Today when I tried to open the attachment I get the ...
4
votes
2answers
242 views

Remotely fingerprint AV software on LAN machines?

Does anyone know of a method to fingerprint machines in the LAN and find out what kind of AV software is installed?
4
votes
3answers
2k views

How to scan USB drive with clamav on Linux

Is there a way to scan the entire drive including auto-run and all partitions, including the master boot record (MBR)?
4
votes
1answer
547 views

Where can a virus or other malware “hide” on common PC and Mac hardware?

I'm looking for a detailed list of locations that viruses can "hide" in modern hardware even after a reboot. Some things that come to mind include Boot BIOS/Firmware CPU Microcode Connected PCI ...
4
votes
1answer
165 views

How does my antivirus determine which CTL is used?

I have imported a trusted root certificate into the Windows local machine list. This works fine with my signed certificates, unless my AV (Bitdefender Antivirus Plus 2012) is set to "scan SSL", in ...
3
votes
4answers
316 views

What is the purpose of EICAR?

For as long as can remember, EICAR has been used to test for the presence of Antivirus systems in email, the file system, or other places. Sometimes the AV solution is so far out of date, that its ...
3
votes
4answers
797 views

To what extent is FREE 3rd party antivirus software better than Windows 8 defender (if any)?

As someone who is not in a position to currently purchase an antivirus suite, I would like to know if having a free Avira or Avast or similar program is worth the overall system performance drop (I ...
3
votes
3answers
478 views

How do polymorphic/metamorphic/self-encrypting/self-changing file infectors know if they have infected a file or not?

If a virus rewrites itself for each infection how would it know if it has infected a file or not? If it keeps infecting the same file soon the whole file structure will be corrupt. For example how ...
3
votes
4answers
324 views

Has any virus attempted to compromise the anti-virus database?

I was using an old version of Norton Anti Virus and the Live Update wouldn't run. The solution was to rename a file. This got me thinking if a virus could replace an anti-virus database with it's own ...
3
votes
2answers
537 views

Why do I get AV alerts when browsing a web page?

I'm using the latest version of Firefox and Windows is up to date. When I was browsing a webpage and clicked a link the browser displayed "connection has been reset" and AVAST poped-up saying "Alert!" ...