Cybercrime Phishing: Phishing online crime - Phishing |
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What is Phishing?
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In computing, phishing is a criminal activity using social engineering techniques. Phishers attempt to fraudulently acquire sensitive information, such as usernames, passwords and credit card details, by masquerading as a trustworthy entity in an electronic communication. eBay and PayPal are two of the most targeted companies, and online banks are also common targets. Phishing is typically carried out by email or instant messaging, and often directs users to give details at a website, although phone contact has been used as well. Attempts to deal with the growing number of reported phishing incidents include legislation, user training, and technical measures.
The first recorded mention of phishing is on the alt.online-service.america-online Usenet newsgroup on January 2, 1996, although the term may have appeared even earlier in the print edition of the hacker magazine 2600. The term phishing is a variant of fishing, probably influenced by phreaking, and alludes to the use of increasingly sophisticated lures to "fish" for a user's financial information and passwords. The word may also be linked to leetspeak, in which ph is a common substitution for f. The popular theory that it is a portmanteau of password harvesting is an example of folk etymology.
Early phishing on AOL
Those who would later phish on AOL during the 1990s originally used fake, algorithmically generated credit card numbers to create accounts on AOL, which could last weeks or even months. After AOL brought in measures in late 1995 to prevent this, early AOL crackers resorted to phishing for legitimate accounts.
Phishing on AOL was closely associated with the warez community that exchanged pirated software. A phisher might pose as an AOL staff member and send an instant message to a potential victim, asking him to reveal his password. In order to lure the victim into giving up sensitive information the message might include text such as "verify your account" or "confirm billing information". Once the victim had submitted his password, the attacker could access and use the victim's account for criminal purposes, such as spamming. Both phishing and warezing on AOL generally required custom-written programs, such as AOHell. Phishing became so prevalent on AOL that they added a line on all instant messages stating: "no one working at AOL will ask for your password or billing information".
After 1997, AOL's policy enforcement with respect to phishing and warez became stricter and forced pirated software off AOL servers. AOL simultaneously developed a system to promptly deactivate accounts involved in phishing, often before the victims could respond. The shutting down of the warez scene on AOL caused most phishers to leave the service, and many phishers — often young teens — grew out of the habit.
Transition from AOL to financial institutions
Capture of AOL account information may have led phishers to misuse credit card information, which then evolved into attacks against online payment systems. The first known direct attempt against a payment system affected E-gold in June 2001, which was followed up by a "post-911 id check" shortly after the September 11 attacks on the World Trade Center. Both were viewed at the time as failures, but can now be seen as early experiments towards more fruitful attacks against mainstream banks. By 2004, phishing was recognized as fully industrialized, in the sense of an economy of crime: specializations emerged on a global scale and provided components for cash which were assembled into a finished attack.
Recent phishing attempts
A chart showing the increase in phishing reports from October 2004 to June 2005.More recent phishing attempts have targeted the customers of banks and online payment services. E-mails supposedly from the Internal Revenue Service have also been used to glean sensitive data from U.S. taxpayers. While the first such examples were sent indiscriminately in the hope of finding a customer of a given bank or service, recent research has shown that phishers may in principle be able to establish what bank a potential victim has a relationship with, and then send an appropriate spoofed email to this victim. Targeted versions of phishing have been termed spear phishing. Social networking sites are also a target of phishing, since the personal details in such sites can be used in identity theft. Experiments show a success rate of over 70% for phishing attacks on social networks. In late 2006 a computer worm took over pages on MySpace and altered links to direct surfers to websites designed to steal login details.
Phishing techniques
Link manipulation
Most methods of phishing use some form of technical deception designed to make a link in an email (and the spoofed website it leads to) appear to belong to the spoofed organization. Misspelled URLs or the use of subdomains are common tricks used by phishers, such as this example URL, http://www.yourbank.com.example.com/. Another common trick is to make the anchor text for a link appear to be a valid URL when the link actually goes to the phishers' site.
An old method of spoofing links used links containing the @ symbol, originally intended as a way to include a username and password in a web link (contrary to the standard). For example, the link http://www.google.com@members.tripod.com/ might deceive a casual observer into believing that the link will open a page on www.google.com, whereas the link actually directs the browser to a page on members.tripod.com, using a username of www.google.com: the page opens normally, regardless of the username supplied. Such URLs were disabled in Internet Explorer, while the Mozilla and Opera web browsers opted to present a warning message and give users the option of continuing to the site or cancelling.
A further problem with URLs has been found in the handling of Internationalized domain names (IDN) in web browsers, that might allow visually identical web addresses to lead to different, possibly malicious, websites. Despite the publicity surrounding the flaw, known as IDN spoofing or a homograph attack, no known phishing attacks have yet taken advantage of it. Phishers have taken advantage of a similar risk, using open URL redirectors on the websites of trusted organizations to disguise malicious URLs with a trusted domain.
Website forgery
Once the victim visits the website the deception is not over. Some phishing scams use JavaScript commands in order to alter the address bar. This is done either by placing a picture of the legitimate entity's URL over the address bar, or by closing the original address bar and opening a new one containing the legitimate URL.
In another popular method of phishing, an attacker uses a trusted website's own scripts against the victim. These types of attacks (known as cross-site scripting) are particularly problematic, because they direct the user to sign in at their bank or service's own web page, where everything from the web address to the security certificates appears correct. In reality, the link to the website is crafted to carry out the attack, although it is very difficult to spot without specialist knowledge. Just such a flaw was used in 2006 against PayPal.
A Universal Man-in-the-middle Phishing Kit, discovered by RSA Security, provides a simple to use interface that allows a phisher to convincingly reproduce any website and capture any log in details entered at the fake site.
Phone phishing
Not all phishing attacks require a fake website. In an incident in 2006, messages that claimed to be from a bank told users to dial a phone number regarding problems with their bank accounts. Once the phone number (owned by the phisher, and provided by a Voice over IP provider) was dialed, prompts told users to enter their account numbers and PIN. Voice phishing sometimes uses fake caller-ID data to give the appearance that the calls come from a trusted organization.
Phishing examples
PayPal phishing example
An example of a phishing email targeted at PayPal users.In an example PayPal phish (right), spelling mistakes in the email and the presence of an IP address in the link (visible in the tooltip under the yellow box) are both clues that this is a phishing attempt. Another giveaway is the lack of a personal greeting, although the presence of personal details is not a guarantee of legitimacy.
SouthTrust Bank example
In this second example, targeted at SouthTrust Bank users, the phisher has used an image to make it harder for anti-phishing filters to detect by scanning for text commonly used in phishing emails.
From: SouthTrust
To: john.smith@example.com
Subject: SouthTrust Bank: Important Notification
Date: Thu, 16 Jun 2005 23:56:30 -0200 (22:56 BRT)
Damage caused by phishing
The damage caused by phishing ranges from loss of access to email to substantial financial loss. This style of identity theft is becoming more popular, because of the ease with which unsuspecting people often divulge personal information to phishers, including credit card numbers, social security numbers, and mothers' maiden names. There are also fears that identity thieves can add such information to the knowledge they gain simply by accessing public records. Once this information is acquired, the phishers may use a person's details to create fake accounts in a victim's name, ruin a victim's credit, or even prevent victims from accessing their own accounts.
It is estimated that between May 2004 and May 2005, approximately 1.2 million computer users in the United States suffered losses caused by phishing, totaling approximately $929 million USD. U.S. businesses lose an estimated $2 billion USD a year as their clients become victims. In the United Kingdom losses from web banking fraud — mostly from phishing — almost doubled to £23.2m in 2005, from £12.2m in 2004, while 1 in 20 users claimed to have lost out to phishing in 2005.
The UK banking body APACS' stance is that "customers must also take sensible precautions...so that they are not vulnerable to the criminal." Similarly, when the first spate of phishing attacks hit the Irish Republic's banking sector in September 2006, the Bank of Ireland initially refused to (and still insists that its policy is not to) cover losses suffered by its customers, although losses to the tune of €11300 were made good.
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