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

learn more… | top users | synonyms

2
votes
3answers
1k views

How to do a virus scan before post attachments in asp.net application

How to do a virus scan before post attachments in asp.net application,when they find a virus on to give up post attachments,otherwise proceed to upload. I wonder if there are any APIs out there where ...
2
votes
3answers
2k views

Do I have a virus on my hosted site?

A few weeks ago I hired an outsourcer from India to build for me a very simple PHP site. I bought PHP hosting and a domain name, and I gave him all the credentials together with the specification of ...
0
votes
2answers
252 views

How could an AV detect a virus that has a chance of not decrypting itself?

If I understand this correctly there is a chance the virus may not decrypt itself at all. How could an AV catch this? In some cases, the decryptor may start with a header whose intent is not ...
1
vote
0answers
1k views

Why do complex viruses tend to be written in assembly? [closed]

For example Simile is extremely complex and is written in assembly. If something is going to be complicated isn't it best NOT to write it in assembly?
20
votes
4answers
2k 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 ...
-1
votes
2answers
9k views

Malware or buggy software gives Low Disk Space warning

Since a few days, I am getting an alert that in my c drive disk space is low. When I verified, free space in my c drive was decreasing hour by hour and there was a stage when it simply said that 0 mb ...
3
votes
2answers
169 views

How could one avoid virus infection via software updates

Almost all useful software get updated with time. Operating system updates, I "guess", might be less stringently checked by the normal anti-virus programs, since their sources could be considered to ...
3
votes
2answers
565 views

How to practically detect current system net traffic?

I know that some viruses or trojans can install rootkits or bootkits to change system's normal behaviour; AFAIK for example filter queries for running processes or even hide active TCP ports. My ...
3
votes
4answers
442 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 ...
21
votes
2answers
1k 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 ...
5
votes
1answer
3k views

What can I do to make sure my computer isn't infected with FinSpy?

What steps have been taken by common free software OS distributions to protect against it? What can Windows users do? What ways are there to rid a system of it?
1
vote
1answer
82 views

Two questions regarding Mixor worm

According to Symantec's write up "it also infects .exe and .scr files in folders containing [RANDOM CHARACTERS].t". What if one of the .exe/.src files is run on the same computer - then all the ...
2
votes
2answers
14k views

How does Remote Access Trojan / Backdoor Software work?

How does the RAT works? I understand it as once we surf the infected website, browser might download the trojan to our PC automatically. Will it executed and auto install in our computer? I can't ...
6
votes
3answers
373 views

How safe are copies of Firefox that are on various Mozilla mirror sites?

If I end up downloading a .dmg or .exe (depending on OS) installer from some mirror site, how can I be sure that a virus or trojan or spyware has not been added? I don't see any mechanism for ...
4
votes
3answers
665 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 ...
0
votes
1answer
384 views

Virus developers groups [closed]

Are there any groups of virus developers around anymore? Like 29A group and bunch of other groups few years ago. They never released their codes, never used then to steal data etc.
2
votes
2answers
541 views

Can a polymorphic/metamorphic worm use a mutex?

Can a polymorphic/metamorphic worm use (the same) mutex? This would solve the problem of grinding the network into the ground and consuming all resources with multiple instances of the worm. Is the ...
-1
votes
1answer
138 views

Would this be plausible for a metamorphic virus? Not repeatedly infecting same system

Would this be plausible for a metamorphic virus? When a new generation (for lack of better word) is created it would hard code a random file name, that would be checked to see if the system was ...
17
votes
2answers
794 views

Is there a real possibility of getting malware by “drive-by”?

I know malware can be gotten by downloading and running stuff, but is there a real possibility of just viewing a webpage or clicking a link and getting one? Assuming using only Firefox / Chrome and ...
1
vote
1answer
436 views

What are the security issues relating to macro enabled MS office documents?

Are there any security issues relating to macro enabled MS office documents?
2
votes
3answers
327 views

Find changes and modifications made to system by application or virus,

I would like to use either Hyper-V or Vmware to take a Clean Base snapshot and a snapshot after an application or virus has made changes so I can then see what was changed between the two images. ...
2
votes
1answer
314 views

How does malware such as Stuxnet and Flamer propagate through USB memory sticks?

The best explanation I found is from this article but it still is unclear to me. Apparently a new vulnerability has been found involving .lnk files where when a folder on the memory stick containing ...
6
votes
4answers
541 views

Would running VMs inside of VMs be a more secure way to study viruses, etc?

I was reading this post on SuperUser, and it made me wonder about security. I've read somewhere else that some viruses/malware/whatever CAN break outside of a VM... and then infect the host OS. BUT, ...
12
votes
3answers
4k views

What file formats are known to be unsafe?

I recently found out pdf's can contain viruses, and from the impression I got its more than a buffer overflow error (I heard it may visit urls automatically but the person sounded unsure) What are ...
2
votes
2answers
247 views

How do viruses know if they have already infected a system or done something?

I know some viruses repeat the same actions over and over again with no break, thus grinding the network to a halt. But others "take a break" from there repetitive actions. For example Nimda ...
3
votes
2answers
617 views

Why does Antivirus Softwares have an Issue with EXE Packers

Im trying to pack an Executable using an Exe Packer like UPX.I packed and checked the File with VirusTotal.com.Here some 9 Antivirus Products say its a Virus actually its a harmless exe.I think the AV ...
4
votes
2answers
4k views

How to detect a virus in a network card?

How can I know that a network card in a server was infected by a virus or not? Are there any methods to check it?
4
votes
5answers
1k views

Clicked on fake “Download Now!” ad on file transfer site (legal file for legit purposes) by accident; does anyone know what measures I should take?

I was sent a file by a coworker via "sendshare" - my first time using the service. The page loaded a bit slowly and the ads came in before the actual download link. I was in a hurry to get the file - ...
6
votes
4answers
602 views

Is there any chance PHP developers themselves implement backdoors in PHP core?

This is not a concern that I personally have,no! In my job environment I've heard from programmers and non programmers that PHP developers always put secret backdoors in PHP that no one has access to ...
0
votes
2answers
2k views

Will virus downloaded to guest OS affect Host OS? [duplicate]

Possible Duplicate: How secure are virtual machines really? False sense of security? If I download a file in Guest Windows XP machine in Vmware Workstation, which is a virus. Can it affect ...
1
vote
2answers
580 views

AVG Website Scan, Chance of 'Potential Threat'?

In a recent question I asked about investigating websites for viruses. The answers were very helpful, I ended up using the AVG website scanner. First I used it on our website and found it was clean, ...
2
votes
2answers
4k views

How to check if a website is sending out a virus?

I'm a webmaster at a company without much knowledge of IT Security. We are running 6 computers connected to a central server that also hosts our website. 3 out of 6 people in the office have gotten ...
-3
votes
2answers
263 views

Will winlock virus really delete information after 12 hours? [closed]

I've got virus which tells that all data will be deleted after 12 hours. I cleaned autorun and now scaning my computer with anti-virus, but still is this message just to scary people or is this virus ...
3
votes
3answers
2k views

Cleaning a virus by mounting the infected hard disk on another machine?

I have a laptop that has been infected with a virus. I am thinking of taking the disk out of the laptop, putting it into an external disk enclosure, and connecting it to a second laptop so I can run ...
1
vote
1answer
1k views

Can a website infect a computer without the user's assistance? [duplicate]

Possible Duplicate: Can you get virus just by visiting a website in chrome I have a hard time believing that drive-by downloads can actually happen without a user's assistance (e.g. without ...
3
votes
3answers
2k views

Writing a sample virus (not harmful)

I don't know if such a question is allowed on this site, sorry if it's not For educational purposes I am asked to write a small virus running on Linux, which should just be able to inject itself into ...
1
vote
0answers
196 views

Hidden Registry Strings - possible rootkit? [closed]

Win server 2003 R2 SP2 - no noticeable issues on the machine. When I create new strings in regedit, I hit refresh and they are gone! I try to re-add and it complains the string already exists. I am ...
2
votes
2answers
469 views

How can I protect content distributed on a linux virtual machine?

What assets am I trying to protect? An unofficial pre-alpha software prototype provided as a reproducible example for evaluation during the scientific peer-review process. The software will be ...
4
votes
4answers
1k views

Cleaning pendrive without infecting

I'm using Ubuntu without ever (knowingly) having had any virus issues. Recently I put a usb pen in a computer in a print shop, and their Windows machine told me that it was infected. I would like to ...
2
votes
1answer
257 views

FireFox Download Source

While downloading the latest version of Firefox for Mac, i took a peek at the source. The names don't look legit but i am not that familiar with how CDNs work. I hit download multiple times and ...
2
votes
2answers
10k views

What are these ip adresses my computer is connected and how do I block them if they are malicious? [closed]

When I execute a netstat command i see several ip-adresses that have connection to my pc and I don't what they are for. These are the ip's. TCP 192.168.1.20:1042 fa-in-f125:5222 ...
1
vote
1answer
946 views

Has my Mac been compromised? [closed]

I am running NOD32 on a Mac running Leopard 10.5.8. When I visited a website, NOD32 automatically detected it as a virus. For some reason I was taken to bing.com and I got a "page not found" error. ...
6
votes
3answers
881 views

How effective is something like Deep Freeze against boot sector infections?

I work for an embedded system manufacturer and on our older generation systems, which are powered by Windows Embedded, a number of customers have been experiencing virus infections. Due to the real ...
5
votes
2answers
506 views

How might an email do damage merely by being opened?

E.g. http://www.dailymail.co.uk/sciencetech/article-2094982/Threat-new-virus-infected-emails-PC-DONT-open-attachments.html?ito=feeds-newsxml Assuming that the user clicks no links and opens no ...
2
votes
1answer
163 views

Is there a tool that puts on a webserver some .html or .php files filled with popular malware like java drive-bys or other browser exploit payloads? [closed]

As mentioned in the title I'm looking for a tool that puts on a webserver some .html or .php files filled with popular malware like java drive-bys or other browser exploit payloads? Maybe there is ...
0
votes
1answer
435 views

Iframe hack / done through FTP?

On two websites which I host for a friend, I found that there is an iframe at the bottom of each site's index.htm file. <iframe src="http://www.kunstsalen.dk" width=1 height=1 style="visibility: ...
3
votes
2answers
252 views

ltd.exe, “Vista Antivirus Security 2012”, any info?

I was taking a look at someone's computer who had a virus. It called itself "Visa Antivirus Security 2012". It turned out to be ltd.exe. It would seemingly randomly block programs, it turns out it had ...
2
votes
2answers
775 views

Online virus scanning service with remote file submission?

I have some links that contain hacking tool and whatnot and I want to pass them to a virus scanning service. The thing is that I don't want to download them to my pc and upload them to their service, ...
3
votes
1answer
3k views

What is Win32/Kryptik.FM?

ESET detected this trojan, but I cannot find any information on the Internet on what it is. Google is only returning links on how to remove it, or what files have been detected to contain it. ...
3
votes
1answer
782 views

Mac sending hundreds of packets to gateway

I've got a user on my work network who brings her personal laptop (macbook) in for work. They've been having some horrendously slow network issues on everything past that hub, so I did some packet ...