Phishing

Phishing is a form of social engineering where attackers deceive people into revealing sensitive information[1] or installing malware such as ransomware. Phishing attacks have become increasingly sophisticated and often transparently mirror the site being targeted, allowing the attacker to observe everything while the victim is navigating the site, and transverse any additional security boundaries with the victim.[2] As of 2020, it is the most common type of cybercrime, with the FBI's Internet Crime Complaint Centre reporting more incidents of phishing than any other type of computer crime.[3]

The term "phishing" was first recorded in 1995 in the cracking toolkit AOHell, but may have been used earlier in the hacker magazine 2600.[4][5][6] It is a variation of fishing and refers to the use of lures to "fish" for sensitive information.[5][7][8]

Measures to prevent or reduce the impact of phishing attacks include legislation, user education, public awareness, and technical security measures.[9] The importance of phishing awareness has increased in both personal and professional settings, with phishing attacks among businesses rising from 72% to 86% from 2017 to 2020.[10]

Types

Email phishing

Phishing attacks, often delivered via email spam, attempt to trick individuals into giving away sensitive information or login credentials. Most attacks are "bulk attacks" that are not targeted and are instead sent in bulk to a wide audience.[11] The goal of the attacker can vary, with common targets including financial institutions, email and cloud productivity providers, and streaming services.[12] The stolen information or access may be used to steal money, install malware, or spear phish others within the target organization.[5] Compromised streaming service accounts may also be sold on darknet markets.[13]

This method of social engineering attack involve sending fraud email or messages that appear to be from a trusted source, such as bank, amazon, or government agency. These messages will typically contain a link or attachment that, when you click, will install malware automatically on the targeted device or redirect them to fake login page of any trusted website where they will be promoted to enter their login credential.

Spear phishing

Spear phishing is a targeted phishing attack that uses personalized emails[14] to trick a specific individual or organization into believing they are legitimate. It often utilizes personal information about the target to increase the chances of success.[15][16][17][18] These attacks often target executives or those in financial departments with access to sensitive financial data and services. Accountancy and audit firms are particularly vulnerable to spear phishing due to the value of the information their employees have access to.[19]

Threat Group-4127 (Fancy Bear) targeted Hillary Clinton's campaign with spear phishing attacks on over 1,800 Google accounts, using the accounts-google.com domain to threaten targeted users.[20][21]

A study on spear phishing susceptibility among different age groups found that 43% of 100 young and 58 older users clicked on simulated phishing links in daily emails over 21 days. Older women had the highest susceptibility, while susceptibility in young users declined over the study, but remained stable in older users.[22]

Whaling and CEO fraud

Whaling attacks use spear phishing techniques to target senior executives and other high-profile individuals[23] with customized content, often related to a subpoena or customer complaint.[24]

CEO fraud involves sending fake emails from senior executives to trick employees into sending money to an offshore account.[25] It has a low success rate, but can result in organizations losing large sums of money.[26]

Clone phishing

Clone phishing is a type of attack where a legitimate email with an attachment or link is copied and modified to contain malicious content. The modified email is then sent from a fake address made to look like it's from the original sender. The attack may appear to be a resend or update of the original email. It often relies on the sender or recipient being previously hacked so the attacker can access the legitimate email.[27][28]

Voice phishing

Main article: Voice phishing

Voice over IP (VoIP) is used in vishing or voice phishing attacks,[29] where attackers make automated phone calls to large numbers of people, often using text-to-speech synthesizers, claiming fraudulent activity on their accounts. The attackers spoof the calling phone number to appear as if it is coming from a legitimate bank or institution. The victim is then prompted to enter sensitive information or connected to a live person who uses social engineering tactics to obtain information.[29] Vishing takes advantage of the public's lower awareness and trust in voice telephony compared to email phishing.[30]

SMS phishing

SMS phishing[31] or smishing[32][33] is a type of phishing attack that uses text messages from a cell phone or smartphone to deliver a bait message.[34] The victim is usually asked to click a link, call a phone number, or contact an email address provided by the attacker. They may then be asked to provide private information, such as login credentials for other websites. The difficulty in identifying illegitimate links can be compounded on mobile devices due to the limited display of URLs in mobile browsers.[35] Smishing can be just as effective as email phishing, as many smartphones have fast internet connectivity. Smishing messages may also come from unusual phone numbers.[36]

Page hijacking

Page hijacking involves redirecting users to malicious websites or exploit kits through the compromise of legitimate web pages, often using cross site scripting. Hackers may insert exploit kits such as MPack into compromised websites to exploit legitimate users visiting the server. Page hijacking can also involve the insertion of malicious inline frames, allowing exploit kits to load. This tactic is often used in conjunction with watering hole attacks on corporate targets.[citation needed]

Calendar phishing

Calendar phishing involves sending fake calendar invitations with phishing links. These invitations often mimic common event requests and can easily be added to calendars automatically.[37] To protect against this form of fraud, former Google click fraud czar Shuman Ghosemajumder recommends changing calendar settings to not automatically add new invitations.[38]

Techniques

Link manipulation

Phishing attacks often involve creating fake links that appear to be from a legitimate organization.[39] These links may use misspelled URLs or subdomains to deceive the user. In the following example URL, http://www.yourbank.example.com/, it can appear to the untrained eye as though the URL will take the user to the example section of the yourbank website; actually this URL points to the "yourbank" (i.e. phishing) section of the example website. Another tactic is to make the displayed text for a link appear trustworthy, while the actual link goes to the phisher's site. To check the destination of a link, many email clients and web browsers will show the URL in the status bar when the mouse is hovering over it. However, some phishers may be able to bypass this security measure.[40]

Internationalized domain names (IDNs) can be exploited via IDN spoofing[41] or homograph attacks[42] to allow attackers to create fake websites with visually identical addresses to legitimate ones. These attacks have been used by phishers to disguise malicious URLs using open URL redirectors on trusted websites.[43][44][45] Even digital certificates, such as SSL, may not protect against these attacks as phishers can purchase valid certificates and alter content to mimic genuine websites or host phishing sites without SSL.[46]

Filter evasion

Phishers have sometimes used images instead of text to make it harder for anti-phishing filters to detect the text commonly used in phishing emails.[47] In response, more sophisticated anti-phishing filters are able to recover hidden text in images using optical character recognition (OCR).[48]

Social engineering

Phishing often uses social engineering techniques to trick users into performing actions such as clicking a link or opening an attachment, or revealing sensitive information. It often involves pretending to be a trusted entity and creating a sense of urgency,[49] like threatening to close or seize a victim's bank or insurance account.[50]

An alternative technique to impersonation-based phishing is the use of fake news articles to trick victims into clicking on a malicious link. These links often lead to fake websites that appear legitimate,[51] but are actually run by attackers who may try to install malware or present fake "virus" notifications to the victim.[52]

History

Main article: List of phishing incidents

Early history

Early phishing techniques can be traced back to the 1990s, when black hat hackers and the warez community used AOL to steal credit card information and commit other online crimes. The term "phishing" is said to have been coined by Khan C. Smith, a well-known spammer and hacker,[53] and its first recorded mention was found in the hacking tool AOHell, which was released in 1995. AOHell allowed hackers to impersonate AOL staff and send instant messages to victims asking them to reveal their passwords.[54][55] In response, AOL implemented measures to prevent phishing and eventually shut down the warez scene on their platform.[56][57]

2000s

In the 2000s, phishing attacks became more organized and targeted. The first known direct attempt against a payment system, E-gold, occurred in June 2001, and shortly after the September 11 attacks, a "post-9/11 id check" phishing attack followed.[58] The first known phishing attack against a retail bank was reported in September 2003.[59] Between May 2004 and May 2005, approximately 1.2 million computer users in the United States suffered losses caused by phishing, totaling approximately US$929 million.[60] Phishing was recognized as a fully organized part of the black market, and specializations emerged on a global scale that provided phishing software for payment, which were assembled and implemented into phishing campaigns by organized gangs.[61][62] The United Kingdom banking sector suffered from phishing attacks, with losses from web banking fraud almost doubling in 2005 compared to 2004.[63][64] In 2006, almost half of phishing thefts were committed by groups operating through the Russian Business Network based in St. Petersburg.[65] Email scams posing as the Internal Revenue Service were also used to steal sensitive data from U.S. taxpayers.[66] Social networking sites are a prime target of phishing, since the personal details in such sites can be used in identity theft;[67] In 2007, 3.6 million adults lost US$3.2 billion due to phishing attacks.[68] The Anti-Phishing Working Group reported receiving 115,370 phishing email reports from consumers with US and China hosting more than 25% of the phishing pages each in the third quarter of 2009.[69]

2010s

Phishing in the 2010s saw a significant increase in the number of attacks. In 2011, the master keys for RSA SecureID security tokens were stolen through a phishing attack.[70][71] Chinese phishing campaigns also targeted high-ranking officials in the US and South Korean governments and military, as well as Chinese political activists.[72][73] According to Ghosh, phishing attacks increased from 187,203 in 2010 to 445,004 in 2012. In August 2013, Outbrain suffered a spear-phishing attack,[74] and in November 2013, 110 million customer and credit card records were stolen from Target customers through a phished subcontractor account.[75] CEO and IT security staff subsequently fired.[76] In August 2014, iCloud leaks of celebrity photos were based on phishing e-mails sent to victims that looked like they came from Apple or Google.[77] In November 2014, phishing attacks on ICANN gained administrative access to the Centralized Zone Data System; also gained was data about users in the system - and access to ICANN's public Governmental Advisory Committee wiki, blog, and whois information portal.[78] Fancy Bear was linked to spear-phishing attacks against the Pentagon email system in August 2015,[79][80] and the group used a zero-day exploit of Java in a spear-phishing attack on the White House and NATO.[81][82] Fancy Bear carried out spear phishing attacks on email addresses associated with the Democratic National Committee in the first quarter of 2016.[83][84] In August 2016, members of the Bundestag and political parties such as Linken-faction leader Sahra Wagenknecht, Junge Union, and the CDU of Saarland were targeted by spear-phishing attacks suspected to be carried out by Fancy Bear. In August 2016, the World Anti-Doping Agency reported the receipt of phishing emails sent to users of its database claiming to be official WADA, but consistent with the Russian hacking group Fancy Bear.[85][86][87] In 2017, 76% of organizations experienced phishing attacks, with nearly half of the information security professionals surveyed reporting an increase from 2016. In the first half of 2017, businesses and residents of Qatar were hit with over 93,570 phishing events in a three-month span.[88] In August 2017, customers of Amazon faced the Amazon Prime Day phishing attack, when hackers sent out seemingly legitimate deals to customers of Amazon. When Amazon's customers attempted to make purchases using the "deals", the transaction would not be completed, prompting the retailer's customers to input data that could be compromised and stolen.[89] In 2018, the company block.one, which developed the EOS.IO blockchain, was attacked by a phishing group who sent phishing emails to all customers aimed at intercepting the user's cryptocurrency wallet key, and a later attack targeted airdrop tokens.[90]

2020s

Phishing attacks have evolved in the 2020s to include elements of social engineering, as demonstrated by the July 15, 2020, Twitter breach. In this case, a 17-year-old hacker and accomplices set up a fake website resembling Twitter's internal VPN provider used by remote working employees. Posing as helpdesk staff, they called multiple Twitter employees, directing them to submit their credentials to the fake VPN website.[91] Using the details supplied by the unsuspecting employees, they were able to seize control of several high-profile user accounts, including those of Barack Obama, Elon Musk, Joe Biden, and Apple Inc.'s company account. The hackers then sent messages to Twitter followers soliciting Bitcoin, promising to double the transaction value in return. The hackers collected 12.86 BTC (about $117,000 at the time).[92]