A black hat (black hat hacker or blackhat) is a computer
hacker
A hacker is a person skilled in information technology who achieves goals and solves problems by non-standard means. The term has become associated in popular culture with a security hackersomeone with knowledge of bug (computing), bugs or exp ...
who violates laws or ethical standards for nefarious purposes, such as
cybercrime
Cybercrime encompasses a wide range of criminal activities that are carried out using digital devices and/or Computer network, networks. It has been variously defined as "a crime committed on a computer network, especially the Internet"; Cyberc ...
,
cyberwarfare
Cyberwarfare is the use of cyberattack, cyber attacks against an enemy State (polity), state, causing comparable harm to actual warfare and/or disrupting vital computer systems. Some intended outcomes could be espionage, sabotage, propaganda, ...
, or malice. These acts can range from
piracy
Piracy is an act of robbery or criminal violence by ship or boat-borne attackers upon another ship or a coastal area, typically with the goal of stealing cargo and valuable goods, or taking hostages. Those who conduct acts of piracy are call ...
to
identity theft
Identity theft, identity piracy or identity infringement occurs when someone uses another's personal identifying information, like their name, identifying number, or credit card number, without their permission, to commit fraud or other crimes. ...
. A black hat is often referred to as a "cracker".
The term originates from 1950s
westerns, with "bad guys" (criminals) typically depicted as having worn black hats and "good guys" (heroes) wearing white ones. In the same way, black hat hacking is contrasted with the more ethical
white hat approach to hacking. Additionally, there exists a third category, called
grey hat hacking, characterized by individuals who hack, usually with good intentions but by illegal means.
Description
Criminals who intentionally enter computer networks with malicious intent are known as "black hat hackers". They may distribute
malware
Malware (a portmanteau of ''malicious software'')Tahir, R. (2018)A study on malware and malware detection techniques . ''International Journal of Education and Management Engineering'', ''8''(2), 20. is any software intentionally designed to caus ...
that steals data (particularly login credentials), financial information, or
personal information
Personal data, also known as personal information or personally identifiable information (PII), is any information related to an identifiable person.
The abbreviation PII is widely used in the United States, but the phrase it abbreviates has fou ...
(such as passwords or credit card numbers). This information is often sold on the
dark web
The dark web is the World Wide Web content that exists on darknets ( overlay networks) that use the Internet but require specific software, configurations, or authorization to access. Through the dark web, private computer networks can communica ...
. Malware can also be used to hold computers hostage or destroy files. Some hackers may also modify or destroy data in addition to stealing it. While hacking has become an important tool for governments to gather intelligence, black hats tend to work alone or with organized crime groups for financial gain.
Black hat hackers may be novices or experienced criminals. They are usually competent infiltrators of computer networks and can circumvent
security protocol
A cryptographic protocol is an abstract or concrete protocol that performs a security-related function and applies cryptographic methods, often as sequences of cryptographic primitives. A protocol describes how the algorithms should be used and in ...
s. They may create malware, a form of software that enables illegitimate access to computer networks, enables the monitoring of victims' online activities, and may lock infected devices. Black hat hackers can be involved in
cyber espionage or protests in addition to pursuing personal or financial gain. For some hackers, cybercrime may be an addictive experience.
History

One of the earliest and most notorious black hat hacks was the 1979 hacking of The Ark by
Kevin Mitnick
Kevin David Mitnick (August 6, 1963 – July 16, 2023) was an American computer security consultant, author, and convicted hacker. In 1995, he was arrested for various computer and communications-related crimes, and spent five years in prison ...
. The Ark computer system was used by
Digital Equipment Corporation
Digital Equipment Corporation (DEC ), using the trademark Digital, was a major American company in the computer industry from the 1960s to the 1990s. The company was co-founded by Ken Olsen and Harlan Anderson in 1957. Olsen was president until ...
(DEC) to develop the
RSTS/E
RSTS () is a multi-user time-sharing operating system developed by Digital Equipment Corporation (DEC, now part of Hewlett-Packard) for the PDP-11 series of 16-bit minicomputers. The first version of RSTS (RSTS-11, #Versions, Version 1) was implem ...
operating system software.
The
WannaCry ransomware attack in May 2017 is another example of black hat hacking. Around 400,000 computers in 150 countries were infected within two weeks. The creation of decryption tools by security experts within days limited the extortion payments to approximately $120,000, or slightly more than 1% of the potential payout.
The notable
data breach
A data breach, also known as data leakage, is "the unauthorized exposure, disclosure, or loss of personal information".
Attackers have a variety of motives, from financial gain to political activism, political repression, and espionage. There ...
es typically published by major news services are the work of black hat hackers. In a data breach, hackers can steal the financial, personal, or digital information of customers, patients, and constituents. The hackers can then use this information to smear a business or government agency, sell it on the dark web, or extort money from businesses, government agencies, or individuals. The
United States
The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...
experienced a record number of 1,862 data breaches in 2021, according to the Identity Theft Resource Center's 2021 Data Breach Report. Data breaches have been on the rise for some time. From 2013 to 2014, black hat hackers broke into
Yahoo
Yahoo (, styled yahoo''!'' in its logo) is an American web portal that provides the search engine Yahoo Search and related services including My Yahoo, Yahoo Mail, Yahoo News, Yahoo Finance, Yahoo Sports, y!entertainment, yahoo!life, an ...
and stole 3 billion customer records, making it possibly the largest data breach ever.
In addition, the adult website
Adult FriendFinder was hacked in October 2016, and over 412 million customer records were taken.
A data breach that occurred between May and July 2017 exposed more than 145 million customer records, making the national credit bureau
Equifax
Equifax Inc. is an American multinational consumer credit reporting agency headquartered in Atlanta, Atlanta, Georgia and is one of the three largest consumer credit reporting agency, consumer credit reporting agencies, along with Experian and T ...
another victim of black hat hacking.
Strategies
Concealing
One of the most famous black hat methods is to utilize nasty "
doorway pages", which are intended to rank highly for specific search queries. Accordingly, the substance of these doorway pages is stowed away from both the clients and the web indexes. Doorway pages are designed to deceive search engines so that they cannot index or rank a website for synonymous keywords or phrases.
Keyword stuffing
Another form of black hat
search engine optimization
Search engine optimization (SEO) is the process of improving the quality and quantity of Web traffic, website traffic to a website or a web page from web search engine, search engines. SEO targets unpaid search traffic (usually referred to as ...
(SEO) is known as keyword stuffing, which involves repeatedly using the same keywords to try to trick search engines. This tactic involves using irrelevant keywords on a webpage (such as on the homepage or in
metadata tags) to make it appear more relevant for particular keywords, deceiving people who visit the site.
Link farming
Link farm
On the World Wide Web, a link farm is any group of websites that all hyperlink to other sites in the group for the purpose of increasing SEO rankings. In graph theoretic terms, a link farm is a clique. Although some link farms can be creat ...
ing occurs when multiple websites or pages link to a particular website. This is done to profit from the
pay-per-click
Pay-per-click (PPC) is an internet advertising model used to drive traffic to websites, in which an advertiser pays a publisher (typically a search engine, website owner, or a network of websites) when the ad is clicked. This differs from more t ...
(PPC) advertisements on these websites or pages. The issue is that the links only point to the specific website because it promises something in return, when in fact they are only there to increase traffic to the desired website and its popularity. These websites are unethical and will damage the credibility of the website's other pages, possibly reducing its income potential.
Shrouding
Shrouding involves showing different content to clients and web search tools. A website may present
search engine
A search engine is a software system that provides hyperlinks to web pages, and other relevant information on World Wide Web, the Web in response to a user's web query, query. The user enters a query in a web browser or a mobile app, and the sea ...
s with information irrelevant to the website's real content. This is done to boost the website's visibility in search results.
Spamdexing
Spamdexing
Spamdexing (also known as search engine spam, search engine poisoning, black-hat search engine optimization, search spam or web spam) is the deliberate manipulation of search engine indexes. It involves a number of methods, such as link building ...
is a form of black hat SEO that involves using software to inject
backlink
From the point of view of a given web resource (referent), a backlink is a regular hyperlink on another web resource (the referrer) that points to the referent. A ''web resource'' may be (for example) a website, web page, or web directory.
A ba ...
s to a website into search engine results. This is done solely to raise the website's ranking in search engines.
Unethical redirects
A
redirect link is considered unethical if it takes the user to a webpage different from the one indicated in the link. For instance, it is unethical to have a link that should take the user to the website "ABC" but instead takes them to "XYZ". Users are tricked into following an unintended path, even though they might not be interested in the website they land on.
Examples of famous black hats
*
Kevin Mitnick
Kevin David Mitnick (August 6, 1963 – July 16, 2023) was an American computer security consultant, author, and convicted hacker. In 1995, he was arrested for various computer and communications-related crimes, and spent five years in prison ...
is one of the most well-known black hat hackers. At one point, he was the most wanted cybercriminal in the world. He hacked into over forty major corporations, including
Motorola
Motorola, Inc. () was an American multinational telecommunications company based in Schaumburg, Illinois. It was founded by brothers Paul and Joseph Galvin in 1928 and had been named Motorola since 1947. Many of Motorola's products had been ...
and
IBM
International Business Machines Corporation (using the trademark IBM), nicknamed Big Blue, is an American Multinational corporation, multinational technology company headquartered in Armonk, New York, and present in over 175 countries. It is ...
, and even the US National Defense warning system. He was taken into custody and incarcerated in 1995. He became a cybersecurity consultant after his release in 2001, utilizing his hacking expertise for white hat hacking.
*
Vladimir Levin is a Russian hacker who, while working with a dial-up connection and a laptop from his
Saint Petersburg
Saint Petersburg, formerly known as Petrograd and later Leningrad, is the List of cities and towns in Russia by population, second-largest city in Russia after Moscow. It is situated on the Neva, River Neva, at the head of the Gulf of Finland ...
apartment in 1994, accessed the accounts of several large corporate customers of
Citibank
Citibank, N.A. ("N. A." stands for "National bank (United States), National Association"; stylized as citibank) is the primary U.S. banking subsidiary of Citigroup, a financial services multinational corporation, multinational corporation. Ci ...
, stealing USD$10.7 million. He ended up spending three years in jail. However, in 2005, an anonymous hacker group claimed responsibility for the theft, stating that they only sold Vladimir the data needed to steal the money.
Other hat types
White hat
An ethical security hacker is referred to as a
white hat or white hat hacker. The term "
ethical hacking" is meant to mean more than just penetration testing. White hat hackers aim to discover any flaws in the current system with the owner's permission. Many organizations engage white hat hackers to enhance their network security through activities such as
vulnerability assessments. Their primary objective is to assist the organization.
Grey hat
A
grey hat
A grey hat (greyhat or gray hat) is a computer hacker or computer security expert who may sometimes violate laws or typical ethical standards, but usually does not have the malicious intent typical of a black hat hacker.
The term came into u ...
is a hacker who typically does not have malicious intent but often violates laws or common ethical standards. A vulnerability will not be illegally exploited by a grey hat, nor will it instruct others on how to do so; however, the grey hat may trade this information for personal gain. A special group of gray hats are
hacktivists, who hack to promote social change.
The ideas of "white hat" and "black hat" hackers led to the use of the term "grey hat" at the end of the 1990s.
Another difference between these types of hackers is how they find vulnerabilities. The black hat will break into any system or network to uncover
sensitive information for personal gain, whereas the white hat does so at the request of their employer or with explicit permission to determine how secure it is against hackers. The grey hat typically possesses the white hat's skills and intentions and the black hat's disregard for permission or laws.
A grey hat hacker might request organizations for voluntary compensation for their activities.
See also
*
BlueHat
*
Cybercrime
Cybercrime encompasses a wide range of criminal activities that are carried out using digital devices and/or Computer network, networks. It has been variously defined as "a crime committed on a computer network, especially the Internet"; Cyberc ...
*
Cyberwarfare
Cyberwarfare is the use of cyberattack, cyber attacks against an enemy State (polity), state, causing comparable harm to actual warfare and/or disrupting vital computer systems. Some intended outcomes could be espionage, sabotage, propaganda, ...
References
{{Reflist
Hacking (computer security)
Cybercrime
Hat, black