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i'm a new linux user and i have my doubts on how exactly linux is much more safer than windows in preventing virus attacks...can anyone clear dis doubt of mine??
The *nix [includes bsd's and linux] architecture is built on security.
Writing viruses for linux is possible but much more difficult than for Windoze.
An important reason also being that OSS keeps evolving at a much faster rate than proprietary software, so it is very difficult for viruses to evolve alongwith.
In 13 years of working with and using Linux I have NEVER met anyone who had been infected with a virus while using Linux. I'm told there are people who have been infected running Linux, but I've also been told that the moon landing was faked.
Also, you'll probably see some FUD (Fear, Uncertainty, and Doubt) and/or propaganda from Microsoft or Windows advocates saying Linux has a greater number of security holes/fixes.
In fact, I believe Microsoft released a report saying that RHEL 4 had a larger number of bug fixes in the first year than Vista did. A brief explanation:
In Linux, bug fixes are often released before the bug is ever even exploited. In Windows, bug fixes aren't released until at least one week (sometimes much longer) AFTER a bug is exploited.
So if you ever hear someone say there are more bug fixes in Linux than in Windows, it is because Linux maintainers and developers (and users, too) are more proactive than Microsoft.
There are at least 3 reasons:
1. The business and development models give no incentive for holding back on SW fixes. The community fixes things as they appear.
2. More eyes on the code. Open Source means there is no limit on who can see the code and find issues.
3. Windows is a bigger target---simply because more damage can be done.
You'll also hear arguments that the fundamental design of Linux is better. I'm not smart enough to comment on that, but I find people like Linus Torvalds to be credible.
Rather long reading, and understanding may take even longer. However, once finished you'll understand infecting POSIX systems is not cutting butter with hot knife as it is with Windows.
A lot of good answers, but none of them, including the link spelled it out in simplest terms.
In Linux, and I assume Unix, each and every file has 'permissions' attached to it. No one without correct permissions can do anything to a file. That includes program applications in use, and also any malware sent to the machine.
Permissions can control read; write; and execute uses of that file. When you look at any file or folder via ls -l you will see something like drwxrwxrwx or maybe I have the order wrong, and on many of these there will be a - to show that class does not have permission for that file for that function.
Permissions can be sent by group; user; and other limitations.
Logged in as a user, on your own machine, you cannot write to your system files. You can use them, but you can't change or modify them; you can't write to them at all.
So, when a virus comes in, it's goal is to write itself to your system files or file.
It cannot be done. Period. You can't; it can't.
That is also why it is discouraged to log in as root, because a virus could then take over your machine just as it does in MS software.
Some of the commands involved with permissions are chmod and chown.
I have received a virus or trojan for Linux, by IP I would guess it came from the Former Soviet Union. Somewhat fearless, I clicked on the attachment, and it asked me for my password.
I believe I have that sucker stored somewhere on my HD if someone wants it give me an e-mail address and I will look for it and pass it on.
It is alleged that 800 viruses have been written for Linux. They simply do not work on Linux.
A lot of the information on this thread involves attacks on your system, invasions via Internet, not virus attempts, which is a different matter.
They do have anti-virus for Linux, this is usually to screen mails being sent to Windows machines via Linux servers.
Worrying about a virius in Linux is about as smart as worrying about
bill gates bank account
Maybe so, but give me a valid e-mail address and I will send you one I got with a spam, if I can find where I stored it, and you can tell us what it did to your machine. I could upload it as an attachment, but somehow that seems like it would not be appreciated.
There was a thread here some 6 months or more ago about the possibility of Linux boxes being infected by Windows native viruses. This was possible through utilities such as WINE, which could execute the viruses, and depending on the configuration of WINE, could escape into the user's home folder and data.
However, this was still limited to the respective user's permissions levels.
There was a thread here some 6 months or more ago about the possibility of Linux boxes being infected by Windows native viruses. This was possible through utilities such as WINE, which could execute the viruses, and depending on the configuration of WINE, could escape into the user's home folder and data.
However, this was still limited to the respective user's permissions levels.
Well, I remember best those viruses could do was to crash Wine. Escaping to user's home directories? Windows viruses? Hmmm ...
First, let us make sure we are not comparing apples and oranges. That number of 800 was stated as mostly security programmer attempts to see if it were possible to create such a virus. They were written and tested in safe environments, and there was no attempt to infect any system outside the safe area. It was reported that none of them were capable of reproducing themselves on a system logged in as user. Is this true? I have no idea, but had no reason to doubt it.
I do stand corrected. I just Googled, and found a Linux virus in the wild in 2001 and one in 2007. Estimates are from 10 to 100 in the wild, but there seemed to be no major impact on Linux users. Some doubt that as many as 10 are in the wild.
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I have it stored as Virus_Hallmark_mail_msg.jsp.html but can't seem to remember why. It is 40726 bytes. The file shows September 28, 2007. I checked my INBOX and it looks like that mail has been deleted, which is what I think I would have done.
Here is a text file report I wrote at the time, which gives a lot of data. The text below was from Khexedit when I examined it. I am guessing its original name was postcard.gif.exe and the tricky part was it functioned in Linux, except it was impotent with no permissions. I have wondered it perhaps it was clever enough to work both in Linux and Windows. Spaces put in to bust link for obvious reasons.
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[mod_edit]Let's take this out all together, shall we?[/mode_edit]
If I had the ambition to reinstall Windows XP again, I would install that virus on my W3115 not connected to the Web, and give it the password to see what happens.
And, further more, I do not agree it is wrong to offer to send it to others, who may be involved in some sort of study on such topics. I do not even understand the statement that I should not offer to send it to someone who knows what it is and wants to study it. If the owners of this URL want to specify that no one can offer to send a Linux virus to someone who wants to study it, that is their right, but as far as I know that has not been decreed. In fact, I think that's how anti-virus companies develop their defenses.
And, not wanting to cause friction on a really good board, I find it somewhat patronizing to be told it is wrong to click on it when I am logged in as user. I made a calculated decision to do so, on a machine which I totally own in the privacy of my own home, believing that it couldn't harm my machine very much when logged in as user. I was right.
One of the things I like most about Linux is all the options one has. And, it seems the later generation of newbies want to reduce those options for everyone to the ones of their own choice. That desire to do it our own way is why we have so many distros.
Last edited by Tinkster; 04-22-2008 at 04:21 AM.
Reason: remove dangerous link altogether
There have been a couple of outbreaks of Linux-only viruses. They tend to attack particular servers and services, because that is the only way that they can self-propagate. Google "linux lion" and "linux ramen" for two examples.
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