Computer Invaders: The 25 Most Infamous PC Viruses of All Time

From the first amateur hackers in the 80s till 2011 when international cyber sabotage is a reality, viruses have illustrated the frightening potential of human ingenuity. Here’s a brief look back how computer viruses have evolved through the most important outbreaks of the last 25 years.

The first PC virus

1. Brain, 1986
More than a decade before anyone had ever heard of Napster, the first PC virus was designed to fight piracy. The author who came up with the word “cyber,” William Gibson called Brain “basically a wheel-clamp for PCs.”

Basit and Amjad Alvi created and marketed medical software in Lahore, Pakistan. They were interested in two things. First, they wanted to check the multi-tasking functionality in the new DOS operating system (so-called “TSR” systems). Secondly, they wanted to see if there are security vulnerabilities in DOS compared to other operating systems such as Unix.

When they realized that DOS was quite vulnerable, they had the idea to write a snippet of software that would monitor how the software and the floppy disks move around. Brain spread virally via 3 1/4-inch disks, and within weeks, the Alvi’s had to change their phone numbers.

25 years after the creation of first PC virus, in early 2011, F-Secure’s Mikko Hypponen went to Lahore, Pakistan to visit the address in the code. He found the Alvi brothers still there, running a successful business. The following video includes the first video interview Amjad and Farooq have given about Brain ever.

Some early fun

Most of the early viruses were variations of the same theme: “Gotcha!” Users knew they’d been infected because that was exactly the point. Like a digital pie in the face.

2. Stoned, 1987
Created by a high school student in New Zealand, Stoned was supposed to be harmless. It simply displayed the message “Your PC is now Stoned!” on your screen. However, as the first virus that infected a PC’s boot sector, Stoned established that viruses could control a computer’s function from the moment it turned on. Bob Dylan should be proud.

3. Form, 1990
Form became one of the most widespread viruses ever. On the 18th of each month, it produced a clicking sound from the PC’s speaker whenever a key was pressed. Annoying, but harmless.

Other variations on this early innocent sort of “gotcha” virus included V-Sign, which displayed a V on your screen. The Walker virus showed an elderly man walking across your screen. Elvira scrolled text in the “A long time ago, in a galaxy far, far away” style a la Star Wars. And then there was Joshi. Every year, on the Joshi’s birthday, this eponymous virus displayed a birthday message. The machine refused to boot up until the user typed “Happy Birthday Joshi.”

4. Michelangelo, 1992
Michelangelo would override everything on a hard drive on specified dates. A variation of Stoned with much crueler intentions, Michelangelo was probably the first computer virus that made international news.

5. VCL, 1992
Virus Creation Laboratory made it easy to whip up a malicious little program by automating virus creation using a simple graphical interface.

Getting Destructive

Early MS-DOS and PC-DOS viruses did some damage to PCs, usually intentionally, but virus writers soon began to actively seek to wreak havoc by actively disabling computers.

6. Happy99, 1999
Happy99 was the first email virus. It greeted you with “Happy New Year 1999” and emailed itself to all  contacts in your address book. Like the very first PC viruses, Happy99 did not cause any real damage, though it did spread to millions of PCs around the world.

7. Monkey, 1993
A distant relative of Stoned, Monkey secretly integrated itself into data files and spread seamlessly. It was the early ancestor of a rootkit, a self-concealing program, and it prevented booting from a floppy disk. When it was removed improperly, Monkey prevented any sort of booting at all.

Upgrading to Windows

In the early 90s, viruses became macro viruses and took on Microsoft’s new OS, Windows. Written in the same languages as applications like Microsoft Word, macro viruses appeared in late 1995. In just three months, they became the most common virus type in the world.

8. Concept, 1995
The first virus that infected Microsoft Word files, Concept became one of the most common viruses in the world because it could infect any OS that could run Word. Share the file, share the virus.

9. Melissa, 1999
Allegedly named after a female exotic dancer familiar to the virus writer, Melissa combined a virus and an email virus. It infected a Word file then emailed itself to all contacts in the user’s address book and became the first virus to span the globe in only hours. Melissa combined the jokey motivations of the early virus writers with the destructiveness of the era. This virus inserted comments from “The Simpsons” into users’ documents. Not so bad. But Melissa could also send out confidential information without the users’ notice. D’oh!

Not long after Melissa, Microsoft virtually eliminated macro viruses by changing how its Visual Basic macro language works within Office applications.

Crashing the network

Before firewalls, computer worms generated huge amounts of network traffic, disrupting systems by pure volume. These worms generally did not affect individual users but they could rock the infrastructure of both private businesses and governments.

10. Code Red, 2001
The first worm that spread without requiring any user interaction at all and thus spread around the world in minutes, Code Red hid from detection and carried out various functions on a cycle. On Days 1-19, it spread itself. From the 20th to the 27th, it launched Denial of Service attacks on various addresses including the White House. And from the 28th day till the end of the month, it rested.

10. Loveletter, 2000
The computer worm that broke millions of hearts, Loveletter is still one of the biggest outbreaks of all time. It spread via email attachment and overwrote many of the crucial files on the PCs it infected. This outbreak was an incredible successful attempt at social engineering. Using the promise of love, it convinced millions to open the attachment, causing an estimated $5.5 billion in damage worldwide. Guess there are a lot of people out there looking for a little love.

12. Slammer, 2003
Network worms require just a few lines of code and vulnerability to spark real world trouble. Slammer took down Bank of America’s ATM network and 911 services in Seattle. Even the air traffic control system was not immune.

13. Sobig, 2003
Sobig was a quick improvement on Fizzer (see below). Some versions waited for a couple of days after infecting a machine before turning affected machines into e-mail proxy servers. The result? Massive spam. AOL alone reported stopping more than 20 million infected messages on one day.

14. Mydoom, 2004
Mydoom spread over email and the Kazaa Peer-to-Peer (P2P) network. It set new records but was old school in the sense that the motive wasn’t monetary. Mydoom executed Distributed Denial-of-Service attack on one particular website and opened a backdoor on infected computers, which left the machine open to remote access.

15. Sasser, 2004
Sasser came in through a vulnerable network ports and slowed or crashed networks from Australia to Hong Kong to the UK.

Money. Money. Money.

In the last decade, the motive for virus writing has become obvious: Money. The technology still tends to be variations on a theme, but modern virus writers utilize advanced user psychology and social engineering to draw users into traps that they’d probably been warned about several times.

16. Fizzer, 2003
Fizzer was the first virus designed to make money. It arrived as an infected attachment. Once opened, it took over infected computers and forced them to send spam.

Ever-evolving threats

As the real-world impact of viruses was felt in the early 90s, business, government, software makers and the Internet security industry put fires out and collaborated to minimize threats. Virus writers, too, evolved to avoid detection, creating advanced malware that could even be programmed to be patient.

17. Cabir, 2003
The first mobile phone virus in history, Cabir targeted Nokia smartphones running the Symbian operating system. It was spread via Bluetooth and proved that whatever shape PCs evolve into, they will be targeted.

18. SDBot, 2003
SDBot was a Trojan horse that bypassed normal security to secretly control a computer. It created a backdoor that allowed the user to do several things including sniff for passwords and the reg codes of games like Half-Life and Need for Speed 2.

19. Haxdoor, 2005
Haxdoor was another Trojan horse that sniffed for passwords and other private data. Later variants had rootkit capabilities. Even Brain used techniques to cloak itself, but Haxdoor employed far more sophisticated methods. A modern rootkit can turn a computer into a zombie computer that can be controlled without the user’s knowledge, sometimes for years.

20. Sony BMI, 2005
In 2005, one of the biggest record companies in the world had the same idea that the Alvi brothers had in 1986: Use a virus to prevent piracy. On its audio CDs, it included a music player program and a rootkit that controlled how the owner could access the audio tracks. The result was a media firestorm and a class-action lawsuit that ended with Sony offering users money and free downloads.

Cyber Sabotage

Computer viruses have had real world effects for decades, but in 2010 a computer virus may have changed the course of history.

In November of 2010, Iranian President Mahmoud Ahmadinejad confirmed that a cyber attack had indeed caused problems with their nuclear centrifuges. And in January of 2011, Russia’s ambassador to NATO said that Stuxnet could cause a “new Chernobyl.”

21. Stuxnet, 2010
An unusually large Windows worm—about a 1000% larger than the typical computer worm, Stuxnet most likely spread through USB device. It infects a system, hides itself with a rootkit and sees if the infected computer is connected to a Siemens Simatic factory system. If the worm finds a connection, it then changes the commands sent from the Windows computer to the PLC Programmable Logic Controllers, i.e., the boxes that actually control the machinery. Once running on the PLC, it looks for a specific factory environment. If this is not found, it does nothing.

F-Secure Labs estimates that it would take more than 10 man-years of work to complete Stuxnet. This complexity and the fact that it could be used to impair the ability of a centrifuge to enrich uranium while providing no monetary gain suggest that Stuxnet was probably developed by a government—though which government is unclear.

22. Storm Worm, 2007
Machiavelli said it’s better to be feared than loved. Seven years after Loveletter, Storm Worm capitalized on our collective fear of bad weather and first spread generally via an email message with the subject line “230 dead as storm batters Europe.” Once the attachment was open, a Trojan backdoor and a rootkit forced the PC to join a botnet. Botnets are armies of zombie computers that can be used to, among other thing, send out tons of spam. And this one sucked in ten million computers.

23. Mebroot, 2008
Mebroot was a rootkit built to hide from the rootkit detectors that quickly became part of many Internet security suites. It is so advanced that if it crashes a PC, Mebroot will send a diagnostic report to the virus writer.

24. Conficker, 2008
Conficker quickly took millions of computers all over the globe. It exploits both flaws along with Windows and weak passwords along with several advanced techniques. Once a system is infected, further malware can be installed and the user is even prevented from visiting the website of most Internet security vendors. More than two years after it was first spotted, more computers are infected by the worm every day. F-Secure’s Chief Research Office Mikko Hypponen has said that in many ways Conficker is still “a great mystery.”

25. 3D Anti Terrorist
This trojanized “game” targets Windows Mobile phones and was spread via freeware sites. Once installed, it starts making calls to expensive numbers leaving you with large charges. This strategy of hijacking a mobile app or cloaking a malicious app is still new, but it’s likely to one of the main ways the virus writers will attack mobile devices.

Where are we 25 years after Brain?

In 2011, a PC running an updated version of Windows 7 is quite secure, especially when running updated security software. Now that we know more about viruses, we know how to fight them, and ideally prevent them. So, hopefully, in 25 years viruses will have gone the way of macro viruses and we won’t have to make a new list.



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Tricks Not Treats: The 5 Scariest Online Threats

The first known use of the term "trick or treat" was found in a November 1927 edition of Blackie, Alberta's Canada Herald: Hallowe’en provided an opportunity for real strenuous fun. No real damage was done except to the temper of some who had to hunt for wagon wheels, gates, wagons, barrels, etc., much of which decorated the front street. The youthful tormentors were at back door and front demanding edible plunder by the word “trick or treat” to which the inmates gladly responded and sent the robbers away rejoicing. "No real damage" from "youthful tormentors?" Sounds a lot like the early days of hacking. Unfortunately those days are long over. “It’s a business,” F-Secure's Chief Research Officer Mikko Hyppönen told Wired UK. “There’s a whole structure there that’s needed,” F-Secure's "Cyber Gandalf" Andy Patel told ITPRO. “An individual can’t just go in and do this now; it’s not a one man job… these are companies.” The cyber crime "industry" has raked in hundreds of millions and possibly even billions of dollars. And it does it, in general, by counting on people to make mistakes. “People do stupid stuff,” Mikko explained. “You cannot patch people.” The first step to avoiding a threat is knowing it exists. So this Halloween as you search for treats online, look out for these tricks. Ransomware F-Secure Labs has warned about malware that holds your digital files hostage to demand a ransom for most of the last decade. But it's in the last year that the threat has burst into the mainstream and become something you can't go a few weeks without hearing about it on the news. How do you avoid this trick? Keep your system software updated and run security software at all times. Make regular backups of every file that matters on your computer and never click on attachments and links in emails that you weren't expecting. Find My iPhone Scam This scam answers the question, "How can losing your iPhone get any worse?" People who use the "Find My iPhone" app have been targeted by criminals who've gotten ahold of their phones with a scam that allows the crooks to gain access to the device and -- possibly -- the owner's most intimate financial details. How do you avoid this? Check the URL before entering any confidential data. Or as Apple says, "You should never enter your Apple account information on any non-Apple website." Phishing Scams As cyber criminals have gone pro, they've gotten better at using old tactics that we thought had faded away -- like email attachments and phishing scams. Like the trick that gives crooks access to stolen iPhones, a phishing scam just tricks you into entering your private credentials into the wrong site. And it then uses those credentials to hack your email, financial accounts, etc. Checking URLs before entering data is crucial because with the explosion of photo editing software and skills, it's now easier than ever to make a fake site look real. Experts believe that one wrong click to a fake site led the chair of a major presidential campaign to expose his entire inbox to the world. Having someone else leak your password Millions and millions of passwords have been leaked in 2016, some from breaches of data that took place years ago. It might not sound scary that your Yahoo! password from 2005 is now public, except if you are still using that password today on a critical account. This is why you need to use strong, unique password for each important account. Yes, remembering all that is almost impossible. So consider using a tool like F-Secure's KEY to manage your passwords. KEY is free to use on one device. Haunted IoT devices As our homes are getting smarter by connecting almost everything to the internet, they're also getting haunted -- by cyber criminals. A botnet is a network of computers that have been hacked and "enslaved." Security expert Brian Krebs was recently hit by a monster attack on his site that he believes was powered by a botnet powered by "'Internet of Things,” (IoT) devices — routers, IP cameras and digital video recorders (DVRs) that are exposed to the Internet and protected with weak or hard-coded passwords." What can you do? So much of this problem requires manufacturers to improve their security. But you can help by keeping every device updated with the latest software from the manufacturer and always changing your default passwords.  [Image by Daniel Lewis | Flickr]

October 21, 2016
dead end

Should We Stop Thinking of Email As Private?

When he was still working in cyber security for the Finnish government, Erka Koivunen met a NATO diplomat that there was "nothing new" about the era we now live in. Foreign envoys have always lived with the constant awareness that their private communications could be "leaked" for their enemies to exploit. "Anything that was written down could eventually be discovered," Erka, who is now an F-Secure Cyber Security Advisor, told me. "So the most sensitive conversations never took place in writing." Given the massive email leaks that have now hit the worlds of business, with the Sony hacks, and politics, with the leaks of U.S. political figures, is this how we should all start thinking? Does everyone alive in the twenty-first century have to operate like a NATO diplomat? Or a C-level executive who knows any word she types could be subpoenaed? Or the campaign chair of a presidential campaign? The answer, unfortunately, seems to be increasingly clear. "Whatever you write, you may need to defend your position in public," Erka said. Relying on an insecure medium The problems with email begin with the general insecurity of it as a means of communication. It's more like sending a postcard than sending a sealed letter, Erka explains. "As soon as the message goes out of your or your company’s systems, you lose control of it," Erka explained. "This is by far the biggest problem of the good-ole-email. Messages can be eavesdropped, altered, delayed, replayed or dropped altogether without you ever knowing." To actually spy on email as it's being transmitted generally requires legal access to telecommunications infrastructure or extraordinary technical knowhow and resources. Think law enforcement or intelligence agencies. Since these groups have a vested interest in cloaking their activities, they had little incentive to engage in the massive sort of leaking of gigabytes of private data we've seen from Wikileaks. However, we appear to be at the end of the era of "the gentleman's agreement" between countries, as cyber policy expert Mara Tam explained on a recent episode of the Risky.Biz podcast. This agreement went something like: "Gentlemen read each other's email, but they don't leak it to the public." The leaks from former CIA contractor Edward Snowden helped make the public aware of how much information the government potentially could access. But the exposure of a private individual's digital communication to the world presents a stark new reality for anyone who conducts business online. "Personal mailboxes store gigabytes’ worth of conversation history that will be a treasure trove for attackers for multiple reasons," Erka said. "There are sensitive discussions about business strategy, customers, competitors, products. There is also internal gossip, badmouthing and other damaging stuff." Activist Naomi Klein told The Intercept that "this sort of indiscriminate dump is precisely what Snowden was trying to protect us from." And we don't yet have a full sense of the potential ways this mass of data can be used against us. A competitor could use private information to tarnish someone’s reputation and hackers can mine the data to prepare for future cyber intrusions or to gain access to your other accounts through password resets. Letting the public decide what's private Leaks have already cost some executives their jobs and could swing the U.S. presidential election. But in a sense, we're all victims of this new risk to all of our privacy. "Whatever you write in an email you have to consider, are you ready for your boss, your spouse, your business partners to read it?" Erka asked. This new reality leads inevitably to the tragedy of self-censorship. Zeynep Tufekci -- a "techno-sociologist" -- ‏has been doing a running commentary on the Wikileaks revelations and is very disturbed by what she's seeing. "People gossiping in internal conversation is not a scandal—but destroying public/private boundaries will paralyze dissent, not the powerful," she tweeted. Wikileaks is releasing more documents than it could ever sift through in the hopes that the newsworthy information will be discerned by interested researchers around the world. But along with potentially relevant items, intensely private information has been revealed. "For example, a suicide attempt was publicized through Podesta indiscriminate dump (Wikileaks tweeted it out)," she noted. "Who will want to be political?" This makes the loss of email seem dire, but perhaps it speaks to a not just a flaw in the medium's security but the medium itself. "The deeper problem with email is that it has never quite settled on a social mode," The New York Times Farhad Manjoo wrote. "An email can be as formal as a legal letter or as tossed off as drive-by insult. This invites confusion." What can you do? So, should you be like that NATO diplomat content to keep all of your deepest secrets out of writing? Can you expect yourself to remove all snark and potentially offensive thoughts from your emails? Should you assume that your email box is like a box of letters in your attic, vulnerable to anyone who can get access to it? These answers are ultimately up to you and how you use -- or don't use -- email. F-Secure security advisor Sean Sullivan has found that young people he's interviewed are increasingly abandoning email as communication tool. "They only have an account -- typically Gmail -- in order to sign up for stuff," he said. If this continues, email is on its way out, whether it's private or not. For now, lawyers, doctors and other professionals with explicit legal responsibilities, email has a much more defined role that cannot be easily abandoned or circumvented. As far as your work email goes, consult your IT staff for guidance as you may be under legal obligation to preserve your data. But for your personal email, Erka suggests you have to at least be aware of how likely you are to be a target and what you can do to contain any potential damage -- besides using a strong unique password for every email account you have and only entering your account information on the secure webpage of your email provider. If you are involved in international politics, for instance, there's no question. You are a target. Hackers are either after your emails or are trying to get access to powerful people in your contacts. If you're someone with no power, no tumultuous relationships and no interest in politics, you're likely not to be on anyone's radar... yet. The problem is no one knows where you'll be in a few years and our inboxes are big enough to last a lifetime. "When everyone is using cloud-based emails like Gmail, there's no need to save space," Erka said. "That's the whole selling point of those services: Never delete anything." If you see the potential for enough damage, you many want these recent leaks as an inspiration to launch a serious spring cleaning of your personal online inboxes, including email and social media. "You may want to delete the messages you don't need and sort the stuff you do want into folders that you take off the web and can store on a secure backup," Erka suggested. Yes, you will lose the convenience of being able to search your Gmail box through a simple interface, but so will potential hackers. He also recommends sharing documents through sharing platforms and cloud services such as Sharepoint, Salesforce or Dropbox. "These links can require separate authentication upon opening and the sender can control how long it will be valid," Erka said. "If the email gets stolen and leaked years later the chances are the link will be invalid by that time." For quick conversations, Sean suggests Wickr, which offers self-destructing messages through a mobile app or a desktop client with easy encryption, something that just doesn't exist for most email. "For professionals, Wickr has a paid service which will retain messages for a legal requirement, and will then securely delete them post-requirement," he said. Regardless of policy, employers have a vested interest in moving their staff away from an over-reliance on email for more than privacy reasons. "Actual phone calls and face-to-face discussions that get out of your chair are probably more useful than email or chat threats," Sean said. "So rather than swap from one to the other – just learn to better utilize what you work with best." These leaks offer a sobering reminder that email is not secure. But, perhaps, the more important message is that it as a means of communication, it was never very smart. [Image by Alan Levine |Flickr]

October 20, 2016

5 Things You Need to Know About the Threat of Election Hacking

Cyber security is playing an starring role in the drama surrounding the question of who will be the next president of the United States. "The security aspect of cyber is very, very tough," Republican nominee for president Donald Trump said, when asked about securing American secrets from cyber attacks during the first debate. "And maybe it’s hardly do-able." Even the integrity of the election has been put into doubt by the threat of hacking -- which may be exactly the point. The questions about cyber intrusions into the electoral system and the wild speculations those intrusions provoke can be hard to put in perspective. So here are five basic premises to help you assess the situation as this historic election transpires. It would be almost impossible to hack the entire U.S. election. The biggest reason this U.S. presidential election is unhackable is that most of it doesn't depend on computers. More than three out of four Americans will vote on a paper ballot this November 8, Techcrunch's Ben Dickson reports. And the fact that all Americans don't vote in the same manner points to the biggest reason you probably couldn't hack the election. Each state has its own system, with some federal guidance. Nearly every state lacks sufficient funding to fully upgrade their systems, hence the reliance on outdated technology. So while voting machines are definitely vulnerable to hacking, hitting just the right ones in a systematic way that just happens to sway the electoral college vote in favor of one candidate would involve both a massive investment of time and money and an even larger serving of luck. But that doesn't mean an election can't be "hacked." “To ‘hack’ a US presidential election, all you need to do is to obviously tamper with one county’s system, then leak that the tampering occurred,” our security advisor Sean Sullivan told Dickson. “Many people will rush to assume that all of the other typical issues that occur may also be the result of hacking — and thus, you’ll end up delegitimizing all of the results.” A delegitimized election equals a  delegitimized winner. You don't even have to hack an election to hack an election. The hacks of the Democratic National Committee and Hillary Clinton's campaign chair John Podesta could end up being far more consequential in swaying the election than hacking either voting processes or actual vote counts -- especially if the resulting leaks end up revealing something extraordinarily damaging to the candidate in the documents being dripped out by Wikileaks. “Owning an election is gold; being able to influence it is silver; knowing the outcome in advance is bronze,” F-Secure cyber security advisor Erka a Koivunen explained. It's pretty clear that someone is at least after the silver in this election. Someone has definitely poking around in the U.S. election system. The United States has been clear that it believes that Russia is trying to hack this election. This month U.S. officials have explicitly stated that the Russians are behind the hack of a contractor that works on the electoral system of the key swing state of Florida. Similar hacks were reported by the states of Arizona and Illinois. U.S. intelligence also believes Russia is behind the hack of Podesta's emails and a security firm believes it found evidence that the nation led by President Vladmir Putin was behind the hack of the DNC. Russian Foreign Minister Sergei Lavrov told CNN that the accusation that it was behind the Podesta hack "flattering." When pressed to confirm or deny his nation's involvement, Lavrov said, “No, we did not deny this, they did not prove it." Trump himself questioned whether the hack actually happened in the second debate and if he's concerned about Russian hacking, he doesn't seem to be showing it. At one point he even -- jokingly, he said later -- asked Russia to hack his opponent's missing emails. Election technology needs to improve quickly. It's safe to say that no matter who is hacking the U.S. elections, the U.S. is probably hacking them, too. The richest nation on Earth is just not engaging, as far as most people can tell, in the leaks that have followed the recent U.S. hacks. In this new era of cyber attacks backed by nation-states or "privateers" employed by nation-states the rules of cyber espionage are unclear and the fog is thick. No matter what happens in 2016, digital technology will play ever-increasing role in both campaigns and election, and the U.S. needs to take steps to ensure the integrity of its elections. Sullivan believes that the Department of Homeland Security should go through with its proposal to declare voting system critical infrastructure and then adapt its defenses to catch up with the threats. “Network monitoring is rapidly becoming a requirement,” he told Techcrunch's Dickson. And voting must be made to feel at least as secure as using your credit card to buy a coffee. “Smartcard technologies are available in several European countries for online identity authentication,” Sullivan said. “They aren’t widely used. If a country such as the United States were to get serious about rolling out such tech, it would be a game changer.” All of this focus on the security of election systems means that there are “more people checking stuff.” The question now is who is putting in more resources -- the attackers or the people doing the checking. [Image by Maryland GovPics | Flickr]

October 13, 2016