"Here You Have" virus

McAfee: New Worm Eats Your AV Software | Maximum PC
Watch  out for the new one. Don't click on unknown links in emails.

The worm is spread by email with a link to a seemingly innocent PDF
file or raunchy WMV download, though users who click will get much more
than they bargained for.

"When a user chooses to manually follow the hyperlink, they will be
prompted to download or execute the virus," McAfee warns. "When run, the
virus installs itself to the Windows directory as CSRSS.EXE (not to be
confused with the valid CSRSS.EXE file within the Windows System
directory). Once infected the worm attempts to send the aforementioned
message to email address book recipients."

McAfee says it can also be spread through accessible remote machines,
mapped drives, and removable media through Autorun replication. Once
infected, the virus attempts to cripple and delete security services,
including popular AV software like AntiVir, Avast, AVG, McAfee, Panda,
and a whole bunch of others.

Keep your antivirus program up to date as well as the definitions. And old antivirus program with recent definitions won't do the job.

Why do people create computer viruses?

Why do People Create Computer Viruses? | Technibble

There are hundreds of thousands of viruses out there (if not
millions) and they often designed for different objectives. Most of them
fall under the following categories:

• To take control of a computer and use it for specific tasks
• To generate money
• To steal sensitive information (credit card numbers, passwords,
  personal details, data etc.)
• To prove a point, to prove it can be done, to prove ones skill or
  for revenge purposes
• To cripple a computer or network

Read the link for more details.

Most of the viruses I find and deal with on a regular basis on client computers generally fall under points 4 and 2 - to prove it can be done and to generate money.

AVG glitch shows iTunes as a Trojan

Technical Bulletins - AVG Software | AVG antivirus & Internet security software support
If you haven't update AVG since July 25th and you have iTunes, AVG might think that iTunes contains a trojan. Update AVG to fix this. If AVG has moved part of iTunes to its vault, click on the above link for the steps to restore the important iTunes files.

Gumblar virus

New "Gumblar" Virus Making the Rounds | Maximum PC

First detected back in March, the 'Gumblar' attacks have been gaining steam lately, growing by as much as 188 percent in just a single week, ScanSafe warned. Gumblar refers to
a Web attack that plants malicious scripts on normally legitimate
websites, which then redirects Google search results on victims' PCs.

New Web Site Drive-By Threat

Web Attack That Poisons Google Results Gets Worse - Business Center - PC World

... The attack, which has intensified in recent days, can be found on
several thousand legitimate Web sites, according to security experts.
It targets known flaws in Adobe's software and uses them to install a
malicious program on victims' machines, CERT said.

... Security experts say that if you're using a fully-patched system with
up-to-date security software, you should be protected from these
attacks. To date, they've worked by hitting the victim with malicious
PDF or Flash files.

Beware of Scareware

Security Fix - Microsoft: Dramatic Rise in 'Scareware' Infections

"Scareware," or programs that masquerade as legitimate security and anti-virus software and then frighten and bully users into paying for them, have emerged as the most prolific and fastest-growing threats facing PC users, according to a biannual security report released this week by Microsoft Corp.

Microsoft found that in the second half of last year, seven of the top 25 malicious software families removed from Windows computers were scareware titles such as Antivirus2008, XPAntivirus, SpywareSecure, and Winfixer. 

More on the Koobface virus

The Facebook Virus Spreads: No Social Network is Safe - ReadWriteWeb

Play it smart. Keep your anti-virus software up to date. Don't click on fake messages like You look just awesome in this new movie.
And don't install the Flash plug-in from anything but the Adobe Flash site.

For more details, click on the link.

A new Facebook virus to watch out for

Facebook hit by virus - The INQUIRER

Koobface spreads by sending notes to friends of someone whose PC has been
infected.

The messages, with subject headers like, "You look just awesome in this new
movie," direct victims to a third-party site where they are asked to download
what it claims is an update of Adobe's Flash player.

Downloading the software means that users end up with an infected computer,
which then takes users to contaminated sites when they try to use search engines
from Google, Yahoo, MSN and Live.com, according McAfee.

Fake You Tube Pages used to spread viruses

Fake YouTube pages used to spread viruses

A program circulating online helps hackers build those fake pages. Users who follow an e-mail pointing them to one of the pages would see an error message that claims the video they want won't play without installing new software first. That error message includes a link the hacker has provided to a malicious program, which delivers a virus.

This has been happening for a while now, but it's still going on. The best thing to do is to NOT download the plugin/codec if a site tells you you need a special program or codec or plug-in to play the video from a site.

If you think you need special software, go to the actual site that distributes the real plug-ins needed. For most, there is Adobe Flash, Java, Quicktime (I recommend Quicktime Alternative) and Windows Media Player (here's the plug-in for Firefox).
If you are using Firefox 3, here is the link to download the Adobe Flash 10 beta (Windows Version). Version 10 works better for Firefox 3. And, sometimes you might need Real Player (I recommend the alternative version here).

Normally a site with a video embedded won't have a direct link to the above sites - the video space will be replaced with a notice that you need a plug-in to play the video. Fake sites will have direct links or pop-ups offering you a special plug-in. Don't be fooled. If you already have the plug-ins that I've mentioned above, and the video won't play, it is most likely fake so run away from the site.

Beware Unknown Audio and Video Codecs - Spyware Infested

How did I get infected in the first place?
I've been seeing more and more people in my line of work with serious spyware infestations. One of the main ways that you can get things like Smitfraud-C, Spylocked, Vundo, Virtumonde and their variations is to download suspicious codecs to supposedly get an on-line video or song to play. Another way is to download and install some sort of software that claims to be a security or system repair program. Most of these are actually spyware or some other nasty thing. Also, if you are using a peer to peer program like Kazaa, Bearshare, Limewire, etc to download music and other files, you need to be careful with the files once you have them. They could contain viruses or spyware or both. Scan them before you open them.

How Do I Keep From Getting Infected?
Heed all of the above. And research something new before downloading and installing it. When in doubt, ask a professional who knows about these things.
Keep your operating system up to date with all the updates that come up. Most of these updates patch security holes that the threats use to get into things and mess things up.
Keep your Java and Adobe Flash up to date. (and manually remove old versions of Java after updating)
Keep your Antivirus program up to date.
Keep your anti-spyware program up to date.
Don't have more than one antivirus program running at one time.
Run a full system scan for viruses and another for spyware regularly, or whenever you think you might have something.
And don't use Internet Explorer. Most threats written to mess up your browser, are written for IE. Use Firefox instead.