World Library  
Flag as Inappropriate
Email this Article

Hacker (computer security)

Article Id: WHEBN0002471540
Reproduction Date:

Title: Hacker (computer security)  
Author: World Heritage Encyclopedia
Language: English
Subject: In the news/Candidates/June 2011, June 2011, Gary McKinnon, Patrick K. Kroupa, DEF CON
Collection: Computer Occupations, Hacking (Computer Security), Identity Theft, Illegal Occupations
Publisher: World Heritage Encyclopedia

Hacker (computer security)

In the computer security context, a hacker is someone who seeks and exploits weaknesses in a computer system or computer network. Hackers may be motivated by a multitude of reasons, such as profit, protest, challenge, enjoyment,[1] or to evaluate those weaknesses to assist in removing them. The subculture that has evolved around hackers is often referred to as the computer underground and is now a known community.[2] While other uses of the word hacker exist that are related to computer security, such as referring to someone with an advanced understanding of computers and computer networks,[3] they are rarely used in mainstream context. They are subject to the longstanding hacker definition controversy about the term's true meaning. In this controversy, the term hacker is reclaimed by computer programmers who argue that someone who breaks into computers, whether computer criminal (black hats) or computer security expert (white hats),[4] is more appropriately called a cracker instead.[5] Some white hat hackers claim that they also deserve the title hacker, and that only black hats should be called "crackers".


  • History 1
  • Classifications 2
    • White hat 2.1
    • Black hat 2.2
    • Grey hat 2.3
    • Elite hacker 2.4
    • Script kiddie 2.5
    • Neophyte 2.6
    • Blue hat 2.7
    • Hacktivist 2.8
    • Nation state 2.9
    • Organized criminal gangs 2.10
  • Attacks 3
    • Security exploits 3.1
    • Techniques 3.2
  • Notable intruders and criminal hackers 4
  • Notable security hackers 5
  • Customs 6
    • Hacker groups and conventions 6.1
  • Consequences for malicious hacking 7
    • India 7.1
    • Netherlands 7.2
    • United States 7.3
  • Hacking and the media 8
    • Hacker magazines 8.1
    • Hackers in fiction 8.2
      • Books 8.2.1
      • Films 8.2.2
    • Non-fiction books 8.3
  • See also 9
  • References 10
  • Further reading 11
  • External links 12


In computer security, a hacker is someone who focuses on security mechanisms of computer and network systems. While including those who endeavor to strengthen such mechanisms, it is more often used by the mass media and popular culture to refer to those who seek access despite these security measures. That is, the media portrays the 'hacker' as a villain. Nevertheless, parts of the subculture see their aim in correcting security problems and use the word in a positive sense. White hat is the name given to ethical computer hackers, who utilize hacking in a helpful way. White hats are becoming a necessary part of the information security field.[6] They operate under a code, which acknowledges that breaking into other people's computers is bad, but that discovering and exploiting security mechanisms and breaking into computers is still an interesting activity that can be done ethically and legally. Accordingly, the term bears strong connotations that are favorable or pejorative, depending on the context.

The subculture around such hackers is termed network hacker subculture, hacker scene or computer underground. It initially developed in the context of phreaking during the 1960s and the microcomputer BBS scene of the 1980s. It is implicated with 2600: The Hacker Quarterly and the alt.2600 newsgroup.

In 1980, an article in the August issue of Psychology Today (with commentary by Philip Zimbardo) used the term "hacker" in its title: "The Hacker Papers". It was an excerpt from a Stanford Bulletin Board discussion on the addictive nature of computer use. In the 1982 film Tron, Kevin Flynn (Jeff Bridges) describes his intentions to break into ENCOM's computer system, saying "I've been doing a little hacking here". CLU is the software he uses for this. By 1983, hacking in the sense of breaking computer security had already been in use as computer jargon,[7] but there was no public awareness about such activities.[8] However, the release of the film WarGames that year, featuring a computer intrusion into NORAD, raised the public belief that computer security hackers (especially teenagers) could be a threat to national security. This concern became real when, in the same year, a gang of teenage hackers in Milwaukee, Wisconsin, known as The 414s, broke into computer systems throughout the United States and Canada, including those of Los Alamos National Laboratory, Sloan-Kettering Cancer Center and Security Pacific Bank.[9] The case quickly grew media attention,[9][10] and 17-year-old Neal Patrick emerged as the spokesman for the gang, including a cover story in Newsweek entitled "Beware: Hackers at play", with Patrick's photograph on the cover.[11] The Newsweek article appears to be the first use of the word hacker by the mainstream media in the pejorative sense.

Pressured by media coverage, congressman Dan Glickman called for an investigation and began work on new laws against computer hacking.[12][13] Neal Patrick testified before the U.S. House of Representatives on September 26, 1983, about the dangers of computer hacking, and six bills concerning computer crime were introduced in the House that year.[13] As a result of these laws against computer criminality, white hat, grey hat and black hat hackers try to distinguish themselves from each other, depending on the legality of their activities. These moral conflicts are expressed in The Mentor's "The Hacker Manifesto", published 1986 in Phrack.

Use of the term hacker meaning computer criminal was also advanced by the title "Stalking the Wily Hacker", an article by Clifford Stoll in the May 1988 issue of the Communications of the ACM. Later that year, the release by Robert Tappan Morris, Jr. of the so-called Morris worm provoked the popular media to spread this usage. The popularity of Stoll's book The Cuckoo's Egg, published one year later, further entrenched the term in the public's consciousness.


Several subgroups of the computer underground with different attitudes use different terms to demarcate themselves from each other, or try to exclude some specific group with whom they do not agree.

Eric S. Raymond, author of The New Hacker's Dictionary, advocates that members of the computer underground should be called crackers. Yet, those people see themselves as hackers and even try to include the views of Raymond in what they see as a wider hacker culture, a view that Raymond has harshly rejected. Instead of a hacker/cracker dichotomy, they emphasize a spectrum of different categories, such as white hat, grey hat, black hat and script kiddie. In contrast to Raymond, they usually reserve the term cracker for more malicious activity.

According to Ralph D. Clifford, a cracker or cracking is to "gain unauthorized access to a computer in order to commit another crime such as destroying information contained in that system".[14] These subgroups may also be defined by the legal status of their activities.[15]

White hat


  • CNN Tech PCWorld Staff (November 2001). Timeline: A 40-year history of hacking from 1960 to 2001
  • Can Hackers Be Heroes? Video produced by Off Book (web series)

External links

  • Apro, Bill; Hammond, Graeme (2005). Hackers: The Hunt for Australia's Most Infamous Computer Cracker. Rowville, Vic: Five Mile Press.  
  • Beaver, Kevin (2010). Hacking for Dummies. Hoboken, NJ: Wiley Pub.  
  • Conway, Richard; Cordingley, Julian (2004). Code Hacking: A Developer's Guide to Network Security. Hingham, Mass: Charles River Media.  
  • Freeman, David H.; Mann, Charles C. (1997). At Large: The Strange Case of the World's Biggest Internet Invasion. New York: Simon & Schuster.  
  • Granville, Johanna (Winter 2003). "Dot.Con: The Dangers of Cyber Crime and a Call for Proactive Solutions".  
  • Gregg, Michael (2006). Certfied Ethical Hacker. Indianapolis, Ind: Que Certification.  
  • Hafner, Katie; Markoff, John (1991). Cyberpunk: Outlaws and Hackers on the Computer Frontier. New York: Simon & Schuster.  
  • Harper, Allen; Harris, Shon; Ness, Jonathan (2011). Gray Hat Hacking: The Ethical Hacker's Handbook (3rd ed.). New York: McGraw-Hill.  
  • McClure, Stuart; Scambray, Joel; Kurtz, George (1999). Hacking Exposed: Network Security Secrets and Solutions. Berkeley, Calif: Mcgraw-Hill.  
  • Russell, Ryan (2004). Stealing the Network: How to Own a Continent. Rockland, Mass: Syngress Media.  
  • Taylor, Paul A. (1999). Hackers: Crime in the Digital Sublime. London: Routledge.  

Further reading

  1. ^ a b  
  2. ^ Blomquist, Brian (May 29, 1999). "FBI's Web Site Socked as Hackers Target Feds". New York Post. 
  3. ^ "The Hacker's Dictionary". Retrieved 23 May 2013. 
  4. ^ Political notes from 2012: September–December.
  5. ^ Raymond, Eric S. "Jargon File: Cracker". Coined ca. 1985 by hackers in defense against journalistic misuse of hacker 
  6. ^ Caldwell, Tracey (22 July 2011). "Ethical hackers: putting on the white hat". Network Security 2011 (7): 10–13.  
  7. ^ See the Jargon File1981 version of the , entry "hacker", last meaning.
  8. ^ "Computer hacking: Where did it begin and how did it grow?". October 16, 2002. 
  9. ^ a b Elmer-DeWitt, Philip (August 29, 1983). "The 414 Gang Strikes Again".  
  10. ^  
  11. ^ "Beware: Hackers at play". Newsweek. September 5, 1983. pp. 42–46, 48. 
  12. ^ "Timeline: The U.S. Government and Cybersecurity". Washington Post. 2003-05-16. Retrieved 2006-04-14. 
  13. ^ a b David Bailey, "Attacks on Computers: Congressional Hearings and Pending Legislation," sp, p. 180, 1984 IEEE Symposium on Security and Privacy, 1984.
  14. ^ Clifford, D. (2011). Cybercrime: The Investigation, Prosecution and Defense of a Computer-Related Crime. Durham, North Carolina: Carolina Academic Press.  
  15. ^ a b Wilhelm, Douglas (2010). "2". Professional Penetration Testing. Syngress Press. p. 503.  
  16. ^ EC-Council.
  17. ^ Moore, Robert (2005). Cybercrime: Investigating High Technology Computer Crime. Matthew Bender & Company. p. 258.  Robert Moore
  18. ^ a b c Moore, Robert (2006). Cybercrime: Investigating High-Technology Computer Crime (1st ed.). Cincinnati, Ohio: Anderson Publishing.  
  19. ^ O'Brien, Marakas, James, George (2011). Management Information Systems. New York, NY: McGraw-Hill/ Irwin. pp. 536–537.  
  20. ^ Thomas, Douglas (2002). Hacker Culture. University of Minnesota Press.  
  21. ^ Andress, Mandy; Cox, Phil; Tittel, Ed (2001). CIW Security Professional. New York, NY: Wiley. p. 638.  
  22. ^ "Blue hat hacker Definition". PC Magazine Encyclopedia. Retrieved May 31, 2010. A security professional invited by Microsoft to find vulnerabilities in Windows. 
  23. ^  
  24. ^  
  25. ^ a b Chabrow, Eric (February 25, 2012). "7 Levels of Hackers: Applying An Ancient Chinese Lesson: Know Your Enemies". GovInfo Security. Retrieved February 27, 2012. 
  26. ^ Gupta, Ajay; Klavinsky, Thomas and Laliberte, Scott (March 15, 2002) Security Through Penetration Testing: Internet Penetration.
  27. ^ Rodriguez, Chris; Martinez, Richard. "The Growing Hacking Threat to Websites: An Ongoing Commitment to Web Application Security" (PDF). Frost & Sullivan. Retrieved 13 August 2013. 
  28. ^ Press, EC-Council (2011). Penetration Testing: Procedures & Methodologies. Clifton, NY: CENGAGE Learning.  
  29. ^ "Gary McKinnon extradition ruling due by 16 October". BBC News. September 6, 2012. Retrieved September 25, 2012. 
  30. ^ "Kevin Mitnick sentenced to nearly four years in prison; computer hacker ordered to pay restitution ..." (Press release).  
  31. ^ Jordan, Tim and Taylor, Paul A. (2004). Hacktivism and Cyberwars. Routledge. pp. 133–134.  
  32. ^ a b Thomas, Douglas (2003). Hacker Culture. University of Minnesota Press. p. 90.  
  33. ^ Artikel 138ab. Wetboek van Strafrecht, December 27, 2012
  34. ^ Swabey, Pete (27 February 2013). "Data leaked by Anonymous appears to reveal Bank of America's hacker profiling operation". Information Age. Retrieved 21 February 2014. 
  35. ^ "Hackers and Viruses: Questions and Answers". Scienzagiovane.  
  36. ^ Staples, Brent (May 11, 2003). "A Prince of Cyberpunk Fiction Moves Into the Mainstream". The New York Times. Mr. Gibson's novels and short stories are worshiped by hackers 


See also

Non-fiction books



Hackers often show an interest in fictional cyberpunk and cyberculture literature and movies. The adoption of fictional pseudonyms,[34] symbols, values and metaphors from these works is very common.[35]

Hackers in fiction

The most notable hacker-oriented print publications are Phrack, Hakin9 and 2600: The Hacker Quarterly. While the information contained in hacker magazines and ezines was often outdated by the time they were published, they enhanced their contributors' reputations by documenting their successes.[32]

Hacker magazines

Hacking and the media

The maximum imprisonment or fine for violations of the Computer Fraud and Abuse Act depends on the severity of the violation and the offender's history of violations under the Act.

  • A computer exclusively for the use of a financial institution or the United States Government, or, in the case of a computer not exclusively for such use, used by or for a financial institution or the United States Government and the conduct constituting the offense affects that use by or for the financial institution or the Government.
  • A computer which is used in or affecting interstate or foreign commerce or communication, including a computer located outside the United States that is used in a manner that affects interstate or foreign commerce or communication of the United States;

18 U.S.C. § 1030, more commonly known as the Computer Fraud and Abuse Act, prohibits unauthorized access or damage of "protected computers". "Protected computers" are defined in as:

United States

Maximum imprisonment is one year or a fine of the fourth category.[33]


Section Offence Punishment
65 Tampering with computer source documents – Intentional concealment, destruction or alteration of source code when the computer source code is required to be kept or maintained by law for the time being in force Imprisonment up to three years, or/and with fine up to 20000 rupees
66 Hacking Imprisonment up to three years, or/and with fine up to 50000 rupees


Consequences for malicious hacking

The computer underground is supported by regular real-world gatherings called bulletin board systems (BBSs), such as the Utopias, provided platforms for information-sharing via dial-up modem. Hackers could also gain credibility by being affiliated with elite groups.[32]

Hacker groups and conventions

The computer underground[1] has produced its own specialized slang, such as 1337speak. Its members often advocate freedom of information, strongly opposing the principles of copyright, as well as the rights of free speech and privacy. Writing software and performing other activities to support these views is referred to as hacktivism. Some consider illegal cracking ethically justified for these goals; a common form is website defacement. The computer underground is frequently compared to the Wild West.[31] It is common for hackers to use aliases to conceal their identities.


Notable security hackers

Notable intruders and criminal hackers

A thorough examination of hacker tools and procedures may be found in Cengage Learning's E|CSA certification workbook.[28]

Tools and Procedures

Keystroke logging
A keylogger is a tool designed to record ("log") every keystroke on an affected machine for later retrieval, usually to allow the user of this tool to gain access to confidential information typed on the affected machine. Some keyloggers use virus-, trojan-, and rootkit-like methods to conceal themselves. However, some of them are used for legitimate purposes, even to enhance computer security. For example, a business may maintain a keylogger on a computer used at a point of sale to detect evidence of employee fraud.
Computer worm
Like a virus, a worm is also a self-replicating program. It differs from a virus in that (a.) it propagates through computer networks without user intervention; and (b.) does not need to attach itself to an existing program. Nonetheless, many people use the terms "virus" and "worm" interchangeably to describe any self-propagating program.
Computer virus
A virus is a self-replicating program that spreads by inserting copies of itself into other executable code or documents. By doing this, it behaves similarly to a biological virus, which spreads by inserting itself into living cells. While some viruses are harmless or mere hoaxes, most are considered malicious.
Trojan horses
A Trojan horse is a program that seems to be doing one thing but is actually doing another. It can be used to set up a back door in a computer system, enabling the intruder to gain access later. (The name refers to the horse from the Trojan War, with the conceptually similar function of deceiving defenders into bringing an intruder into a protected area.)
Social engineering can be broken down into four sub-groups:
  • Intimidation As in the "angry supervisor" technique above, the hacker convinces the person who answers the phone that their job is in danger unless they help them. At this point, many people accept that the hacker is a supervisor and give them the information they seek.
  • Helpfulness The opposite of intimidation, helpfulness exploits many people's natural instinct to help others solve problems. Rather than acting angry, the hacker acts distressed and concerned. The help desk is the most vulnerable to this type of social engineering, as (a.) its general purpose is to help people; and (b.) it usually has the authority to change or reset passwords, which is exactly what the hacker wants.
  • Name-dropping The hacker uses names of authorized users to convince the person who answers the phone that the hacker is a legitimate user him or herself. Some of these names, such as those of webpage owners or company officers, can easily be obtained online. Hackers have also been known to obtain names by examining discarded documents (so-called "dumpster diving").
  • Technical Using technology is also a way to get information. A hacker can send a fax or email to a legitimate user, seeking a response that contains vital information. The hacker may claim that he or she is involved in law enforcement and needs certain data for an investigation, or for record-keeping purposes.
Hackers who use this technique must have cool personalities, and be familiar with their target's security practices, in order to trick the system administrator into giving them information. In some cases, a help-desk employee with limited security experience will answer the phone and be relatively easy to trick. Another approach is for the hacker to pose as an angry supervisor, and when his/her authority is questioned, threaten to fire the help-desk worker. Social engineering is very effective, because users are the most vulnerable part of an organization. No security devices or programs can keep an organization safe if an employee reveals a password to an unauthorized person.
Social engineering
In the second stage of the targeting process, hackers often use Social engineering tactics to get enough information to access the network. They may contact the system administrator and pose as a user who cannot get access to his or her system. This technique is portrayed in the 1995 film Hackers, when protagonist Dade "Zero Cool" Murphy calls a somewhat clueless employee in charge of security at a television network. Posing as an accountant working for the same company, Dade tricks the employee into giving him the phone number of a modem so he can gain access to the company's computer system.
A rootkit is a program that uses low-level, hard-to-detect methods to subvert control of an operating system from its legitimate operators. Rootkits usually obscure their installation and attempt to prevent their removal through a subversion of standard system security. They may include replacements for system binaries, making it virtually impossible for them to be detected by checking process tables.
Spoofing attack (phishing)
A spoofing attack involves one program, system or website that successfully masquerades as another by falsifying data and is thereby treated as a trusted system by a user or another program — usually to fool programs, systems or users into revealing confidential information, such as user names and passwords.
Packet analyzer
A packet analyzer ("packet sniffer") is an application that captures data packets, which can be used to capture passwords and other data in transit over the network.
Password cracking
Password cracking is the process of recovering passwords from data that has been stored in or transmitted by a computer system. Common approaches include repeatedly trying guesses for the password, trying the most common passwords by hand, and repeatedly trying passwords from a "dictionary", or a text file with many passwords.
Brute-force attack
Password guessing. This method is very fast when used to check all short passwords, but for longer passwords other methods such as the dictionary attack are used, because of the time a brute-force search takes.
Finding vulnerabilities
Hackers may also attempt to find vulnerabilities manually. A common approach is to search for possible vulnerabilities in the code of the computer system then test them, sometimes reverse engineering the software if the code is not provided.
Vulnerability scanner
A vulnerability scanner is a tool used to quickly check computers on a network for known weaknesses. Hackers also commonly use port scanners. These check to see which ports on a specified computer are "open" or available to access the computer, and sometimes will detect what program or service is listening on that port, and its version number. (Firewalls defend computers from intruders by limiting access to ports and machines, but they can still be circumvented.)


A security exploit is a prepared application that takes advantage of a known weakness.[27] Common examples of security exploits are File Transfer Protocol (FTP), Hypertext Transfer Protocol (HTTP), PHP, SSH, Telnet and some Web pages. These are very common in Web site and Web domain hacking.

Security exploits

In order to do so, there are several recurring tools of the trade and techniques used by computer criminals and security experts.

  1. Network enumeration: Discovering information about the intended target.
  2. Vulnerability analysis: Identifying potential ways of attack.
  3. Exploitation: Attempting to compromise the system by employing the vulnerabilities found through the vulnerability analysis.[26]

A typical approach in an attack on Internet-connected system is:


Groups of hackers that carry out organized criminal activities for profit.[25]

Organized criminal gangs

Intelligence agencies and cyberwarfare operatives of nation states.[25]

Nation state

Hacktivism can be divided into two main groups:

A hacktivist is a hacker who utilizes technology to publicize a social, ideological, religious or political message.


A blue hat hacker is someone outside computer security consulting firms who is used to bug-test a system prior to its launch, looking for exploits so they can be closed. Microsoft also uses the term BlueHat to represent a series of security briefing events.[22][23][24]

Blue hat

A neophyte ("newbie", or "noob") is someone who is new to hacking or phreaking and has almost no knowledge or experience of the workings of technology and hacking.[18]


A script kiddie (also known as a skid or skiddie) is an unskilled hacker who breaks into computer systems by using automated tools written by others (usually by other black hat hackers), hence the term script (i.e. a prearranged plan or set of activities) kiddie (i.e. kid, child—an individual lacking knowledge and experience, immature),[21] usually with little understanding of the underlying concept.

Script kiddie

A social status among hackers, elite is used to describe the most skilled. Newly discovered exploits circulate among these hackers. Elite groups such as Masters of Deception conferred a kind of credibility on their members.[20]

Elite hacker

A grey hat hacker lies between a black hat and a white hat hacker. A grey hat hacker may surf the Internet and hack into a computer system for the sole purpose of notifying the administrator that their system has a security defect, for example. They may then offer to correct the defect for a fee.[18] Grey hat hackers sometimes find the defect of a system and publish the facts to the world instead of a group of people. Even though grey hat hackers may not necessarily perform hacking for their personal gain, unauthorized access to a system can be considered illegal and unethical.

Grey hat

A "black hat" hacker is a hacker who "violates computer security for little reason beyond maliciousness or for personal gain" (Moore, 2005).[17] Black hat hackers form the stereotypical, illegal hacking groups often portrayed in popular culture, and are "the epitome of all that the public fears in a computer criminal".[18] Black hat hackers break into secure networks to destroy, modify, or steal data; or to make the network unusable for those who are authorized to use the network. Black hat hackers are also referred to as the "crackers" within the security industry and by modern programmers. Crackers keep the awareness of the vulnerabilities to themselves and do not notify the general public or the manufacturer for patches to be applied. Individual freedom and accessibility is promoted over privacy and security. Once they have gained control over a system, they may apply patches or fixes to the system only to keep their reigning control. Richard Stallman invented the definition to express the maliciousness of a criminal hacker versus a white hat hacker who performs hacking duties to identify places to repair.[19]

Black hat


This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.

Copyright © World Library Foundation. All rights reserved. eBooks from Project Gutenberg are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.