Top 10 Hilarious Viruses, Trojans and Worms

Updated: August 25, 2012

Virus, Trojan, Worm - the very words conjure up crossbones and skulls, the symbol of danger. These malicious programs are the scourge of the Internet, the proof that every innovative and useful technology has an equivalent downside - one that has the most adverse consequences at times. They steal your passwords, corrupt your files memory and OS, open backdoors to your systems, install quirky programs that replicate and spread, and generally cause your computer to behave abnormally.

But there was a time not so long ago when viruses were written just for the fun of it - not to create any real harm, but rather to see if they worked. The creators were usually extremely clever young programmers who spent most of their time in front of their computers. Though the files spread rapidly from one system to another, all they did was produce some funny faces or a cascade of raindrops on your screen. But then, these form just a drop in the ocean of malware that roams through the Internet.

While the consequences of these deadly programs are certainly no laughing matter, there are a few of them that bring an inadvertent smile to your face by virtue of their names, by the graphics they display on execution, or just by the sheer newsworthiness of their exploits. Here are the 10 viruses, Trojans, and worms that caused a little anxiety, some humorous moments, and a lot of confusion.

Did it tickle your funny bone or go straight to your heart? Mum's the word!

1. The "Very Funny" or "I Love You" Virus: This one hit the Internet in the year 2000 and corrupted image and music files on user systems. Identified initially by the words "I love you" or "Joke: Very Funny" in the subject line of an email, the virus was later passed around as newer, more malicious versions that overwrote important files needed to boot the computer. These masqueraded as Mother's Day messages or Lithuanian flirting techniques - some email came with the tag "Let's meet for a cup of coffee," in Lithuanian, of course. Bolder versions took advantage of the scare created by their predecessors, and pretended to be representatives from anti-virus software providers. They asked users to execute the attachment to eradicate all viruses from their computers!


Rats! And I used to love Saturdays!

2. The HPS Virus: The first of its kind written for the Windows 98 OS, this virus took its name from a dreaded disease transmitted by rats. Hantavirus Pulmonary Syndrome (HPS) is known to cause acute respiratory distress in the human body, but its digital namesake was nowhere near as harmful. If present on your system, the HPS virus went into action on Saturdays and flipped over uncompressed bitmaps horizontally. In plain English, it produced a mirror image of your screen. An interesting snippet about this virus: HPS hit the Web in early 1998,even before the Windows 98 operating system was available for commercial use.


Is this why you say NO to drugs?

3. The Stoned or Marijuana Virus: A virus belonging to the stone age of the computer era, this one infected the early DOS systems through floppy disks. First seen in New Zealand in 1988, the original version did not cause any real damage; it simply displayed the message, "Your computer is stoned. Legalize Marijuana" on your screen. However the 90 odd variants of the stoned virus (with names as random as Donald Duck, Hawaii, Rostov, Smithsonian, StonedMutation and more) did do considerable damage to the Master Boot Record and File Allocation Table in your hard disk.


Where were the privacy laws when you needed them?

4. The PolyPoster Virus: Remember how your talking parrot could embarrass you no end if you had any secrets to hide? Well, this virus took on where Polly left off. Known as a macro virus, the PolyPoster not only infected your MS Word files, it posted them to public Usenet newsgroups without your knowledge, under the tempting title "Important Monica Lewinsky Info." The virus strayed into the computers of all those who read these documents, which explains the Lewinsky connection - the virus writer obviously hoped to capitalize on the Clinton-Lewinsky scandal that dominated headlines in 1998. Popular discussion groups that played host to your most confidential and personal documents (thanks to the PolyPoster virus) were, alt.hacker,,, alt.windows95 and alt.skinheads.


Caricature? Cartoon? No, Clinton.

5. The Caric-A Worm: Former US president Bill Clinton provided a lot of fodder for the gossip mills during his tenor at the White House, and as late as 2002 as this famous worm proved. Also known as the Bill Clinton and the MyLife-B worm, this malicious program was activated after opening an email's attachment and displayed a cartoon of Clinton playing the saxophone equipped with a bra popping out of the sax's mouth. The writers of this worm tried to be clever by adding a line to the end of the email, supposedly from anti-virus vendor McAfee, which claimed the email contained no viruses.


Hidden agenda behind the hilarity.

6. The Wurmark Worm: Appearing on the Internet in 2005, the Wurmark-F worm was disguised as a picture of a funny looking old man. Once inside your computer, the worm installed a Trojan, which in turn allowed remote hackers to take control of your infected system. Your computer was then at their beck and call and used to propagate the worm further along the Web. The worm also deleted files randomly from your system, and mailed itself to all your Outlook contacts, using your mail id.


The brain behind it all.

7. The Brain Virus: The brainchild of two Pakistani brothers in 1986, this virus was not meant to be a virus at all. The siblings had written it with the intent to protect their medical software from being pirated. It ended up being the first ever virus to infect the PC. Known by various names, including Lahore, Pakistani, Pakistani Brain, Brain-A, UIUC, Ashar, and Pakistani flu, this pretty-large virus affected the boot sector, changed the disk label to (c)Brain, and displayed the text:

Welcome to the Dungeon (c) 1986 Brain & Amjads (pvt) Ltd VIRUS_SHOE RECORD V9.0 Dedicated to the dynamic memories of millions of viruses who are no longer with us today - Thanks GOODNESS!! BEWARE OF THE er..VIRUS : this program is catching program follows after these messages....$#@%$@!!

in affected boot sectors. It also ate up 7 KB of storage space and slowed down the floppy drive. Perhaps the duo were telling the truth when they said they meant no harm, because they gave out their names, address, and phone numbers in another similar message, asking those affected to contact them for a vaccine. Following a spate of irate calls from the United States and other western countries, they had to resort to a change in number!


How safe is your phone?

8. The Skulls Trojan horse: The rapid advances in the field of mobile technology meant that the malware guys were not far behind. The year 2004 saw this Trojan horse unleashed on Nokia smartphones that ran the Symbian operating system. Users infected with Skulls A found their screen icons replaced with ominous skulls and crossbones, and their handsets being reduced to mere telephones. They could only make and receive calls, other smart functions were disabled. Skulls or Skulls A spawned a series of alphabetical versions, like B, C and L each affecting the phones in a different manner. Version B rendered the phone almost useless just like A, but did not display skulls; C tried to disable the F-Secure anti-virus software; L was probably the most dangerous version - it pretended to be the F-Secure mobile anti-virus solution. All versions of the Trojan snuck the Cabir worm into the phones. This proof-of-concept malware for mobile phones spread through Bluetooth connections and used up the handset's battery power by constantly searching for other devices with open Bluetooth connections to infect.


Bet you didn't know - Mosquito bites cause more than Malaria.

9. The Mosquito Trojan horse: The Symbian OS was the target of another bug in 2004 - this time, the Mosquito Trojan. In another instance of an anti-piracy measure, the software infected phones when they downloaded illegal copies of Mosquito, a game designed for mobile smartphones. Once resident on the handsets, the Trojan sent out text messages at exorbitant costs to premium numbers in the UK, Germany, the Netherlands, and Switzerland, without the knowledge of its users. Vaccinating this one was easy - all those infected had to do was uninstall the game, which I'm sure they would have done once they saw their sky-high phone bills.


Are open Windows the cue for hackers entry?

10. The Cuebot-K Worm: Microsoft and controversy seem to go hand in hand. The software giant came in for some harsh criticism for its anti-piracy software, Windows Genuine Advantage (WGA). Users not only claimed that it was a form of spyware, they also alleged that it opened up their systems to malware via the Internet. The company issued an update to appease irate users, but to add to Microsoft's troubles, virus writers took advantage of this, and came up with the Cuebot-K worm. This 2006 program spread through the Web pretending to be the said update, and landed up in mailboxes supposedly from known AOL contacts. It launched itself when the system booted, and horror of horrors, displayed a message that removal or stoppage of the service would result in system instability. Hiding behind the "Windows Genuine Advantage Validation Notification" name, the worm opens up a backdoor to allow in hackers who then take control of user systems.

In this day and age, malware is no longer harmless. Hackers are at it with a vengeance - they want money more than fame. With more at stake, it is imperative that you protect your computer from the huge volume of malicious software that is unleashed on the Internet every day. Installing the best anti-virus program and keeping up to date with your security patches are not going be enough though - you have to be savvy enough to dodge the bugs that do get past your security software. As this list would have taught you, no attachments are perfectly safe and links embedded in emails are always risky propositions. Keep your wits about you, and use them when it really matters to keep your system free from infection.