Phishing: The basics

Phishing is a method of trying to gather personal information using deceptive e-mails and websites. Typically, a phisher sends an e-mail disguised as a legitimate business request. Because the best defense is a skeptical user, here's how to be on your guard against phishing.

Phishing is a method of trying to gather personal information using deceptive e-mails and websites. Typically, a phisher sends an e-mail disguised as a legitimate business request. For example, the phisher may pass himself off as a real bank asking its customers to verify financial data. (So phishing is a form of "social engineering".) The e-mail is often forged so that it appears to come from a real e-mail address used for legitimate company business, and it usually includes a link to a website that looks exactly like the bank's website. However, the site is bogus, and when the victim types in passwords or other sensitive information, that data is captured by the phisher. The information may be used to commit various forms of fraud and identity theft, ranging from compromising a single existing bank account to setting up multiple new ones.

Early phishing attempts were crude, with telltale misspellings and poor grammar. Since then, however, phishing e-mails have become remarkably sophisticated. Phishers may pull language straight from official company correspondence and take pains to avoid typos. The fake sites may be near-replicas of the sites phishers are spoofing, containing the company's logo and other images and fake status bars that give the site the appearance of security. Phishers may register plausible-looking domains like aolaccountupdate.com, mycitibank.net or paypa1.com (using the number 1 instead of the letter L). They may even direct their victims to a well-known company's actual website and then collect their personal data through a faux pop-up window.

Can phishing attacks be prevented?

Companies can reduce the odds of being targeted, and they can reduce the damage that phishers can do (more details on how below). But they can't really prevent it. One reason phishing e-mails are so convincing is that most of them have forged "from" lines, so that the message looks like it's from the spoofed company. There's no way for an organization to keep someone from spoofing a "from" line and making it seem as if an e-mail came from the organization.

A technology known as sender authentication does hold some promise for limiting phishing attacks, though. The idea is that if e-mail gateways could verify that messages purporting to be from, say, Citibank did in fact originate from a legitimate Citibank server, messages from spoofed addresses could be automatically tagged as fraudulent and thus weeded out. (Before delivering a message, an ISP would compare the IP address of the server sending the message to a list of valid addresses for the sending domain, much the same way an ISP looks up the IP address of a domain to send a message. It would be sort of an Internet version of caller ID and call blocking.)

Although the concept is straightforward, implementation has been slow because the major Internet players have different ideas about how to tackle the problem. It may be years before different groups iron out the details and implement a standard. Even then, there's no way of guaranteeing that phishers won't find ways around the system (just as some fraudsters can fake the numbers that appear in caller IDs). That's why, in the meantime, so many organizations—and a growing marketplace of service providers—have taken matters into their own hands.

How can companies reduce the chance of being targeted by a phishing attack?

In part, the answer has to do with NOT doing silly or thoughtless things that can increase your vulnerability. Now that phishing has become a fact of life, companies need to be careful about how they use e-mail to communicate with customers. For example, in May 2004, Wachovia's phones started ringing off the hook after the bank sent customers an e-mail instructing them to update their online banking user names and passwords by clicking on a link. Although the e-mail was legitimate (the bank had to migrate customers to a new system following a merger), a quarter of the recipients questioned it.

As Wachovia learned, companies need to clearly think through their customer communication protocols. Best practices include giving all e-mails and webpages a consistent look and feel, greeting customers by first and last name in e-mails, and never asking for personal or account data through e-mail. If any time-sensitive personal information is sent through e-mail, it has to be encrypted. Marketers may wring their hands at the prospect of not sending customers links that would take them directly to targeted offers, but instructing customers to bookmark key pages or linking to special offers from the homepage is a lot more secure. That way, companies are training their customers not to be duped.

It also makes sense to revisit what customers are allowed to do on your website. They should not be able to open a new account, sign up for a credit card or change their address online with just a password. At a minimum, companies should acknowledge every online transaction through e-mail and one other method of the customer's choosing (such as calling the phone number on record) so that customers are aware of all online activity on their accounts. And to make it more difficult for phishers to copy online data-capture forms, organizations should avoid putting them on the website for all to see. Instead, organizations should require a secured log-in to access e-commerce forms.

At the end of the day, though, better authentication is the best way to decrease the likelihood that phishers will target your organization. 

What plans should my company have in place before a phishing incident occurs?

Before your organization becomes a target, establish a cross-functional anti-phishing team and develop a response plan so that you're ready to deal with any attack. Ideally, the team should include representatives from IT, internal audit, communications, PR, marketing, the web group, customer service and legal services.

This team will have to answer some hard questions, such as:

* Where should the public send suspicious e-mails involving your brand? Set up a dedicated e-mail account, such as fraud@domainname.com, and monitor it closely.

* What should call center staff do if they hear a report of a phishing attack? Make sure that employees are trained to recognize the signs of a phishing attack and know what to tell and ask a customer who may have fallen for a scam.

* How and when will your organization notify customers that an attack has occurred? You might opt to post news of new phishing e-mails targeting your company on your website, reiterating that they are not from you and that you didn't and won't ask for such information.

* Who will take down a phishing site? Larger companies often keep this activity in-house; smaller companies may want to outsource.

  • If you keep the shut-down service in-house, a good response plan should outline whom to contact at the various ISPs to get a phisher site shut down as quickly as possible. Also, identifying law enforcement contacts at the FBI and the Secret Service ahead of time will improve your chances of bringing the perpetrator to justice.
  • If a vendor is used, decide what the vendor can do on your behalf. You may want to authorize representatives to send e-mails and make phone calls, but have your legal department handle any correspondence involving legal action.

* When will the company take action against a phishing site, such as feeding it inaccurate information or exploiting vulnerabilities in its coding? Talk out the many pros and cons beforehand.

* How far will you go to protect customers? Decide how much information about identity theft you'll give to customers who fall for a scam, and how this information will be delivered. You should also talk through scenarios in which you will monitor or close and re-open affected accounts.

* Are you inadvertently training your customers to fall for phishing scams? Educate the sales and marketing teams about characteristics of phishing e-mails. Then, make sure legitimate e-mails don't set off any alarms.

How can we quickly find out if a phishing attack has been launched using our company's name?

Sometimes a new phish announces itself violently, as an organization's e-mail servers get pummeled with phishing e-mails that are bouncing back to their apparent originator. There are other ways to learn about an attack, though—either before or after it occurs.

a) Monitor for fraudulent domain name registrations.

Phishers often set up the fake sites several days before sending out phishing e-mails. One way to stop them from swindling your customers is to find and shut down these phishing sites before phishers launch their e-mail campaigns. You can outsource the search to a fraud alert service. These services use technologies that scour the Web looking for unauthorized uses of your logo or newly registered domains that contain your company's name, either of which might be an indication of an impending phishing attack. This will give your company time to counteract the strike.

b) Set up a central inbox. To do this, organizations typically set up one e-mail address where all suspected phishing e-mails are directed, with an address such as fraud@domainname.com or phish@domainname.com. Ideally, this central inbox should be monitored 24/7.

The easiest and most effective way to find out if your organization is being targeted by phishers is simply by giving the general public a way to report phishing attacks. "It's your customers and noncustomers who are going to be the ones that tell you that the phish is out there," said one security manager interviewed for a case study published in

c) Watch your Web traffic. Internet Storm Center recommends that by examining web traffic logs and looking for spikes in referrals from specific, heretofore unknown IP addresses, CSOs may be able to zero in on sites used for large-scale phishing attacks.

After gathering victims' information, many phishing sites then redirect the victim to a log-in page on the real website the phisher is spoofing.

How can we help our customers avoid falling for phishing?

People who know about phishing stand a better chance of resisting the bait. "The best defense is that a consumer has heard of phishing and is unlikely to respond," says Patricia Poss, an attorney with the Bureau of Consumer Protection at the Federal Trade Commission. People must be trained to think twice about replying to any e-mail or pop-up that requests personal information.

Teach employees how to recognize spoofed e-mail. Similarly, warn your customers about the dangers of phishing, and let them know you'll never ask for their account number, password, Social Security number or any other personal information via e-mail. Train them to avoid clicking on e-mail links to reach you and instead to type your company's URL directly into a new browser window.

However, there's only so much that customer education can do. The onus is also on the organization to limit the damage by shutting down the phishing site.

If an attack does happen, how should we respond?

Once a phishing attack occurs, the goal for the organization is to get the phishing site shut down as quickly as possible. This limits the window of opportunity in which the phisher can collect personal information. With any phishing attack, organizations should take three steps (or hire a firm to take these steps for them).

Step 1) Gather basic information about the attack. This should include screen shots of the website plus the URL.

Step 2) Contact the ISP (or whoever is hosting the website). Explain the situation and ask that the site be shut down. Many phishing sites are launched on hacked computers, so in a best-case scenario, taking down the site is simply a matter of contacting a website's owners, pointing them to the URL of the webpage, and asking them to remove the offending content (and patch their web servers). 

Step 3) Contact law enforcement. Although this is an important step, be warned that it isn't necessarily the most effective way to get the site shut down quickly. The FBI and Secret Service are more concerned with patterns and big busts than individual ones, and until a customer has fallen for a scam and suffered damages, there may have been no law broken. Nevertheless, agents may be able to intervene on your behalf—and who knows, your case may be part of the bigger picture investigation needed to shut down a given fraudster. (This has happened. In May 2005, a 20-year-old Texas man was sentenced to almost four years in prison for phishing.)

By establishing a relationship with law enforcement, you'll come to understand when agents want information about what kinds of attacks. For instance, the bank in the aforementioned CSOcase study gets a compact disc from its vendor with information about each phish, and a copy of that CD is then passed on to the FBI, which looks for patterns or anomalies in the attacks.

Does all this sound like too much for your company? Then pay someone else to do it for you. The marketplace is brimming right now with companies that will do the dirty work.

[ Related: 10 companies that can help you fight phishing ]

Responders at a good service provider will have expertise in working their way up the network stream seeking someone who can and will shut down the site. They try to work with the ISP or Web hosting company, and then if necessary contact the domain name registrar that's directing the URL to a given IP address. They'll send e-mails and faxes; they'll make phone calls. If necessary, they'll send notices threatening legal action. Often, when the site is hosted outside the United States, they'll seek help from local groups of first responders organized by CERT/CC at Carnegie Mellon. The end result? The phishing website might be up for hours instead of days.

How might phishing attacks evolve in the near future?

At the same time, phishers have also grown more sophisticated in their use of e-mail address lists. A phishing e-mail targeting a regional credit union, for example, may be sent only to customers who use ISPs located in that same area. The latest and perhaps ultimate personalization? A technique known as "spear phishing," in which e-mails are customized for particular users, for example executives at certain kinds of companies. 

Meanwhile, as customers become more savvy about the risks of divulging personal information, fraudsters are looking for ways to gather information without the victims' knowledge. This is often done with a method known as pharming. Like phishing, pharming aims to collect personal information from unsuspecting victims. The difference is that pharming doesn't rely on e-mail solicitation to ensnare its victims. Instead, this attack method essentially tinkers with the road maps that computers use to navigate the Web, such that large numbers of users can wind up giving personal data to a bogus site even if they've typed in a legitimate URL.

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