Cyber attack definition
Simply put, a cyber attack is an attack launched from one or more computers against another computer, multiple computers or networks. Cyber attacks can be broken down into two broad types: attacks where the goal is to disable the target computer or knock it offline, or attacks where the goal is to get access to the target computer's data and perhaps gain admin privileges on it.
7 types of cyber attack
To achieve those goals of gaining access or disabling operations, a number of different technical methods are deployed by cybercriminals. There are always new methods proliferating, and some of these categories overlap, but these are the terms that you're most likely to hear discussed.
- Denial of service
- Man in the middle
- SQL injection
- Zero-day exploits
Malware — Short for malicious software, malware can refer to any kind of software, no matter how it's structured or operated, that "is a designed to cause damage to a single computer, server, or computer network," as Microsoft puts it. Worms, viruses, and trojans are all varieties of malware, distinguished from one another by the means by which they reproduce and spread. These attacks may render the computer or network inoperable, or grant the attacker root access so they can control the system remotely.
Phishing — Phishing is a technique by which cybercriminals craft emails to fool a target into taking some harmful action. The recipient might be tricked into downloading malware that's disguised as an important document, for instance, or urged to click on a link that takes them to a fake website where they'll be asked for sensitive information like bank usernames and passwords. Many phishing emails are relatively crude and emailed to thousands of potential victims, but some are specifically crafted for valuable target individuals to try to get them to part with useful information.
Denial of service — A denial of service attack is a brute force method to try stop some online service from working properly. For instance, attackers might send so much traffic to a website or so many requests to a database that it overwhelms those systems ability to function, making them unavailable to anybody. A distributed denial of service (DDoS) attack uses an army of computers, usually compromised by malware and under the control of cybercriminals, to funnel the traffic towards the targets.
Man in the middle — A man in the middle attack (MITM) is a method by which attackers manage to interpose themselves secretly between the user and a web service they're trying to access. For instance, an attacker might set up a Wi-Fi network with a login screen designed to mimic a hotel network; once a user logs in, the attacker can harvest any information that user sends, including banking passwords.
SQL injection — SQL injection is a means by which an attacker can exploit a vulnerability to take control of a victim's database. Many databases are designed to obey commands written in the Structured Query Language (SQL), and many websites that take information from users send that data to SQL databases. In a SQL injection attack, a hacker will, for instance, write some SQL commands into a web form that's asking for name and address information; if the web site and database aren't programmed correctly, the database might try to execute those commands.
Zero-day exploits — Zero-days are vulnerabilities in software that have yet to be fixed. The name arises because once a patch is released, each day represents fewer and fewer computers open to attack as users download their security updates. Techniques for exploiting such vulnerabilites are often bought and sold on the dark web — and are sometimes discovered by government agencies that controversially may use them for their own hacking purposes, rather than releasing information about them for the common benefit.
Recent cyber attacks
Deciding which cyber attacks were the worst is, arguably, somewhat subjective. Those that made our list did so because they got the most notice for various reasons — because they were widespread, perhaps, or because they were signals of a larger, scary trend.
Without further ado, here are the biggest cyber attacks in recent history:
WannaCry was a ransomware attack that spread rapidly in May of 2017. Like all ransomware, it took over infected computers and encrypted the contents of their hard drives, then demanded a payment in Bitcoin in order to decrypt them. The malware took particular root in computers at facilities run by the United Kingdom's NHS.
Malware isn't anything new, though. What made WannaCry significant and scary was the means it used to propagate: it exploited a vulnerability in Microsoft Windows using code that had been secretly developed by the United States National Security Agency. Called EternalBlue, the exploit had been stolen and leaked by a hacking group called the Shadow Brokers. Microsoft had already patched the vulnerability a few weeks before, but many systems hadn't upgraded. Microsoft was furious that the U.S. government had built a weapon to exploit the vulnerability rather than share information about the hole with the infosec community.
Petya was just another piece of ransomware when it started circulating via phishing spam in 2016; its main claim to fame was that it encrypted the master boot record of infected machines, making it devilishly difficult for users to get access to their files.
Then, abruptly in June of 2017, a much more virulent version of the malware started spreading. It was different enough from the original that it was dubbed NotPetya; it originally propagated via compromised Ukrainian accounting software and spread via the same EternalBlue exploit that WannaCry used. NotPetya is widely believed to be a cyberattack from Russia against Ukraine, though Russia denies it, opening up a possible era of states using weaponized malware.
While this one might not have been as high-profile as some of the others on this list, it deserves a spot here due to the sheer amount of money involved. Ether is a Bitcoin-style cryptocurrency, and $7.4 million in Ether was stolen from the Ethereum app platform in a manner of minutes in July. Then, just weeks later came a $32 million heist. The whole incident raised questions about the security of blockchain-based currencies.
The massive credit rating agency announced in July of 2017 that "criminals exploited a U.S. website application vulnerability to gain access to certain files," getting personal information for nearly 150 million people. The subsequent fallout enraged people further, especially when the site Equifax set up where people could see if their information had been compromised seemed primarily designed to sell Equifax services.
Ed Szofer, CEO of SenecaGlobal, says the Equifax breach is particularly bad "because they had already been told about the fix — it needed to be implemented in a tool called Apache Struts that they use — well before the breach even happened. And yet they failed to do so fully in a timely manner. To prevent such breaches from happening requires a shift in culture and resources; this was not a technical issue, as the technical fix was already known. Equifax certainly had the resources, but it clearly did not have the right culture to ensure the right processes were in place and followed."
This massive hack of Yahoo's email system gets an honorable mention because it actually happened way back in 2013 — but the severity of it, with all 3 billion Yahoo email addresses affected, only became clear in October 2017. Stolen information included passwords and backup email addresses, encrypted using outdated, easy-to-crack techniques, which is the sort of information attackers can use to breach other accounts. In addition to the effect on the account owners, the breach could spawn a revisiting of the deal by which Verizon bought Yahoo, even though that deal had already closed.
The truly scary thing about this breach is that the culture of secrecy that kept it under wraps means that there's more like it out there. "No one is excited to share a breach, for obvious PR reasons," says Mitch Lieberman, director of research at G2 Crowd. "But the truth eventually comes out. What else do we not know?"
On February 28, 2018, the version control hosting service GitHub was hit with a massive denial of service attack, with 1.35 TB per second of traffic hitting the popular site. Although GitHub was only knocked offline intermittently and managed to beat the attack back entirely after less than 20 minutes, the sheer scale of the assault was worrying; it outpaced the huge attack on Dyn in late 2016, which peaked at 1.2 TB per second.
More troubling still was the infrastructure that drove the attack. While the Dyn attack was the product of the Mirai botnet, which required malware to infest thousands of IoT devices, the GitHub attack exploited servers running the Memcached memory caching system, which can return very large chunks of data in response to simple requests.
Memcached is meant to be used only on protected servers running on internal networks, and generally has little by way of security to prevent malicious attackers from spoofing IP addresses and sending huge amounts of data at unsuspecting victims. Unfortunately, thousands of Memcached servers are sitting on the open internet, and there has been a huge upsurge in their use in DDoS attacks. Saying that the servers are "hijacked" is barely fair, as they'll cheerfully send packets wherever they're told without asking questions.
Just days after the GitHub attack, another Memecached-based DDoS assault slammed into an unnamed U.S. service provider with 1.7 TB per second of data.
Cyber attack statistics
If you want to understand just what's going on in the murky world of cybercrime, it's best to dive into the numbers, which only seem to be going up. The number of unique "cyberincidents" in the second quarter of 2018, as defined by Positive Technologies, was 47 percent higher than the number from just a year previous. And those attacks are becoming increasingly precise: 54 percent are targeted, rather than part of mass campaigns.
Willie Sutton famously said that he robbed banks "because that's where the money is," so perhaps it's not a surprise that Positive reported a big spike in attacks on cryptocurrency platforms, given the increasingly lucrative nature of that technology. Overall, cybercrime will net its perpetrators around $1.5 trillion in 2018. Individual cybercriminals can expect to make about 10 to 15 percent more than their offline equivalents, and it's estimated that that around 10 percent of all laundered criminal money comes from cybercrime proceeds.
If you're worried about your phone's safety, you should be—mobile attacks are on the rise. In the third quarter of 2018, Kaspersky Labs the number of malicious mobile installation packages was up by nearly a third when compared to just the previous few months. But there's an easy way to avoid those attacks, as Norton says that 99.9 percent of those packages come from unofficial "third party" app stores.
Cyber attack maps
It can take a lot of effort to comb through all those numbers (and really, we're just scratching the surface and providing a few nuggets here—by all means follow the links for more details). So you can see the why someone might prefer all that info presented in an easy-to-grasp visual medium like a cyber attack map. These futuristic displays show what attacks are emerging from what countries and focusing on what targets, and give the impression of offering a bird's-eye view of the current internet threat landscape.
The problem is that an impression is all they really have to offer. Most of the data they display isn't live, and it certainly isn't comprehensive. But they can be useful in starting conversations about security, getting students interested in cyber security, and serving as sales tools for cyber security tool companies. (Many security experts dismissively refer to them as "pew pew" maps.)
Cyber attack prevention
Looking for tips on how to prevent falling prey to cyber attacks like these? CSO has you covered:
- How small businesses can fend off cyberattacks and data breaches
- If you do suffer a cyberattack, here are some tips for responding and working with law enforcement
- Point-of-sale terminals are a vector for malware and data theft — be sure yours are secure
- The government and businesses can work together to fight cyber attacks