Cybercrime Phishing: Phishing online crime - Anti-phishing Techniques |
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Anti-phishing Techniques
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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.
Anti-phishing
There are several different techniques to combat phishing, including legislation and technology created specifically to protect against phishing.
Social responses
One strategy for combating phishing is to train users to deal with phishing attempts. User education can be promising, especially where training provides direct feedback to the user on his success (or otherwise).[45] One newer phishing tactic, which uses phishing emails targeted at a specific company, known as spear phishing, has been harnessed to train users at various locations, including West Point Military Academy. In a June 2004 experiment with spear phishing, 80% of 500 West Point cadets who were sent a fake email were tricked into revealing personal information.
Users can take steps to avoid phishing attempts by slightly modifying their browsing habits. Users who are contacted about an account needing to be "verified" (or any other topic used by phishers) can contact the company that is the subject of the email to check that the email is legitimate, or can type in a trusted web address for the company's website into the address bar of their browser to bypass the link in the suspected phishing message.
Nearly all legitimate email messages from companies to their customers will contain an item of information that is not readily available to phishers. Some companies, like PayPal, always address their customers by their username in emails, so if an email addresses a user in a generic fashion ("Dear PayPal customer") it is likely to be an attempt at phishing. Emails from banks and credit card companies will often include partial account numbers. However, recent research has shown that typical users do not distinguish between the first few digits and the last few digits of an account number. This is a significant problem since the first few digits often are the same for all clients of one financial institution. One should always be suspicious if the message does not contain specific personal information. Phishing attempts in early 2006, however, used such highly personalized information, making it unsafe to rely on personal information alone as a sign that a message is legitimate. Furthermore, another recent study concluded in part that the presence of this information does not significantly affect the success rate of phishing attacks, suggesting that most users do not pay attention to such details anyway.
The Anti-Phishing Working Group, an industry and law enforcement association, has suggested that conventional phishing techniques could become obsolete in the future as people are increasingly aware of the social engineering techniques used by phishers. They propose that pharming and other uses of malware will become more common tools for stealing information.
Technical responses
Anti-phishing measures have been implemented as features embedded in browsers, as extensions or toolbars for browsers, and as part of website login procedures. The following are some of the main approaches to the problem.
Helping users identify legitimate sites
Since phishing is based on impersonation, preventing it depends on users having some reliable way to identify the sites they are dealing with. For example, some anti-phishing toolbars display the real domain name for the visited website. The petname extension for Firefox lets users type in their own labels for websites, so they can later recognize when they are back at the correct site. If the site is a suspect, then the software may either warn the user or block the site outright.
Alerting users to fraudulent websites
Another popular approach to fighting phishing is to maintain a list of known phishing sites and to check websites against the list. Microsoft's new IE7 browser, Mozilla Firefox 2.0, and Opera all contain this type of anti-phishing measure. Firefox 2 uses Google anti-phishing software. Opera 9.1 uses live blacklists from PhishTank and GeoTrust, as well as live whitelists from GeoTrust. Some implementations of this approach send the visited URLs to a central service to be checked, which has raised concerns about compromising the user's privacy. According to a report by Mozilla in late 2006, Firefox 2 was found to be more effective than Internet Explorer 7 at detecting fraudulent sites in a study by an independent software testing company.
An approach introduced in mid-2006 involves switching to using a special DNS service that filters out known phishing domains, which will work with any browser. This is similar in principle to using a hosts file to block web adverts.
To mitigate the problem of phishing sites spoofing a victim site and embedding its images (such as logos) in a spoof site, several site owners have responded by altering the images to send a message to the visitor. If the images were not requested in the normal way by visiting the real page then a warning that the site is fraudulent can be substituted for the usual image, or the original image can be moved to a new filename and the original permanently replaced with a warning.
Augmenting password logins
Bank of America is one of several websites that ask users to select a personal image, and display this user-selected image with any forms that request a password. Users are instructed to only enter a password when they see the image they selected; if the correct image does not appear, they are expected to recognize that the site is not legitimate. However, a recent study suggests few users refrain from entering their password when images are absent. This feature (like other forms of two-factor user authentication) is also susceptible to other attacks, such as those suffered by Scandinavian bank Nordea in late 2005, and Citibank in 2006.
Security skins are a related technique that involves overlaying a user-selected image across the login form as a visual cue that the form is legitimate. However, unlike the website-based image schemes, this image is shared between the user and the browser, not between the user and the website. The scheme also relies on a mutual authentication protocol, which makes it less vulnerable to attacks that user-only authentication schemes are vulnerable to.
Eliminating phishing mail
Spam filters can also help by reducing the number of phishing emails that users receive.
Monitoring and takedown
Several companies offer banks and other entities likely to suffer from phishing scams 24/7 services to monitor, analyze and assist in shutting down phishing websites. Individuals can contribute by reporting phishing to both volunteer and industry groups, such as PhishTank.
Legal responses
On January 26, 2004, the U.S. Federal Trade Commission filed the first lawsuit against a suspected phisher. The defendant, a Californian teenager, allegedly created and used a webpage designed to look like the America Online website, so that he could steal credit card information. Other countries have followed the lead of the U.S. by tracing and arresting phishers. A phishing kingpin, Valdir Paulo de Almeida, was arrested in Brazil for leading one of the largest phishing crime rings, which in 2 years stole between $18 and $37 million USD. UK authorities jailed two men in June 2005 for their role in a phishing scam, in a case connected to the U.S. Secret Service Operation Firewall, which targeted notorious "carder" websites. In 2006 eight people were arrested by Japanese police on suspicion of phishing fraud by creating bogus Yahoo Japan Web sites, netting themselves 100 million yen ($870 thousand USD). The arrests continued in 2006 with the FBI Operation Cardkeeper detaining a gang of sixteen in the U.S. and Europe.
In the United States, Senator Patrick Leahy introduced the Anti-Phishing Act of 2005 on March 1, 2005. The federal anti-phishing bill proposes that criminals who create fake web sites and spam bogus emails in order to defraud consumers could receive a fine up to $250,000 and receive jail terms of up to five years. The UK has strengthened the legal arsenal against phishing with the Fraud Act 2006, which introduces a general offence of fraud that can carry up to a ten year sentence, and prohibits writing or possessing phishing kits with intent to commit fraud.
Companies have also joined the effort to crack down on phishing. On March 31, 2005, Microsoft filed 117 federal lawsuits in the U.S. District Court for the Western District of Washington. The lawsuits accuse "John Doe" defendants of using various methods to obtain passwords and confidential information. March 2005 also saw Microsoft partner with the Australian government to teach law enforcement officials how to combat various cyber crimes, including phishing. Microsoft announced a planned further 100 lawsuits outside the U.S. in March 2006, followed by the commencement, as of November 2006, of 129 lawsuits mixing criminal and civil actions.
AOL reinforced its efforts against phishing in early 2006 with three lawsuits seeking a total of $18 million USD under the 2005 amendments to the Virginia Computer Crimes Act, and Earthlink has joined in by helping to identify six men subsequently charged with phishing fraud in Connecticut.
In January 2007, Jeffrey Brett Goodin of California became the first defendant convicted by a jury under the provisions of the CAN-SPAM Act of 2003. He was found guilty of sending thousands of e-mails to America Online users, while posing as AOL's billing department, which prompted customers to send personal and credit card information. He faces 101 years in prison for the CAN-SPAM violation and ten other counts including wire fraud, unauthorized use of credit cards, and misusing AOL's trademark.
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