Crime is most commonly defined as a violation of law that is punishable by the entity responsible for that law.
While criminal violations and ethical violations are not identical, there is clearly overlap when laws themselves embody ethical principles.
One opposite of legal behavior is criminal behavior; one opposite of ethical behavior is nihilistic behavior (in this sense, you can regard it as a denial of ethical meaning)
Fortunately, computer science itself, like mathematics, is not a fertile area for crime.
Unfortunately, computer technology is a tool, and like all tools, it can be used for good or for ill.
While computer technology often is an adjunct to many crimes (for example, someone uses a hard drive as a bludgeon), it can integral, such as the very prevalent (and profitable) crime of ransomware.
The widespread adoption of technology is creating many venues for crime; the ever-popular 419 / advance-fee scams.
According to RSA; credit card fraud, account takeover, identity theft particularly prevalent.
Ransomware
Identity theft and account takeover
As you can see from the Wikipedia page, it's hard to use a single word to characterize the group "Anonymous"; maybe "group" isn't even an accurate word.
Whatever Anonymous might be, it certainly receives credit for various acts of "hacktivism".
From Wikileaks "About" page: "WikiLeaks specializes in the analysis and publication of large datasets of censored or otherwise restricted official materials involving war, spying and corruption. It has so far published more than 10 million documents and associated analyses."
Not the exclusive province of the Internet; public release of data about individuals in order to harass or otherwise embarrass has long been done. The Internet however makes for a substantially more powerful platform for these type of attacks.
Information brokers have the ethically interesting business of selling other people's information without their permission.
The Senate's Commerce Committee issued in 2013 a comprehensive report on this industry. Particularly concerning are the sections on how "financially vulnerable" segments of the populace are targeted.