The Art of Deception: Controlling the Human Element of Security (4 page)

THE ENGINEER TRAP It is widely known that head-hunter firms use social engineering to recruit corporate talent. Here's an example of how it can happen.

In the late 1990s, a not very ethical employment agency signed a new client, a company looking for electrical engineers with experience in the telephone industry. The honcho on the project was a lady endowed with a throaty voice and sexy manner that she had learned to use to develop initial trust and rapport over the phone.

The lady decided to stage a raid on a cellular phone service provider to see if she could locate some engineers who might be tempted to walk across the street to a competitor. She couldn't exactly call the switch board and say, "Let me talk to anybody with five years of engineering experience." Instead, for reasons that will become clear in a moment, she began the talent assault by seeking a piece of information that appeared to have no sensitivity at all, information that company people give out to almost anybody who asks.

The First Call: The receptionist The attacker, using the name Didi Sands, placed a call to the corporate offices of the cellular phone service. In part, the conversation went like this: Receptionist: Good afternoon. This is Marie, how may I help you? Didi: Can you connect me to the Transportation Department?

R: I'm not sure if we have one, I'll look in my directory. Who's calling? D: It's Didi. R: Are you in the building, or... ? D: No, I'm outside the building. R: Didi who? D: Didi Sands. I had the extension for Transportation, but I forgot what it was. R: One moment.

To allay suspicions, at this point Didi asked a casual, just making conversation question designed to establish that she was on the "inside," familiar with company locations.

D: What building are you in - Lakeview or Main Place? R: Main Place. (pause) It's 805 555 6469.

To provide herself with a backup in case the call to Transportation didn't provide what she was looking for, Didi said she also wanted to talk to Real Estate. The receptionist gave her that number, as well. When Didi asked to be connected to the Transportation number, the receptionist tried, but the line was busy.

At that point Didi asked for a third phone number, for Accounts Receivable, located at a corporate facility in Austin, Texas. The receptionist asked her to wait a moment, and went off the line. Reporting to Security that she had a suspicious phone call and thought there was something fishy going on? Not at all, and Didi didn't have the least bit of concern. She was being a bit of a nuisance, but to the receptionist it was all part of a typical workday. After about a minute, the receptionist came back on the line, looked up the Accounts Receivable number, tried it, and put Didi through.

The Second Call: Peggy The next conversation went like this:

Peggy: Accounts Receivable, Peggy. Didi: Hi, Peggy. This is Didi, in Thousand Oaks. P: Hi, Didi. D: How ya doing? P: Fine. Didi then used a familiar term in the corporate world that describes the charge code for assigning expenses against the budget of a specific organization or workgroup:

D: Excellent. I have a question for you. How do I find out the cost center for a

particular department? P: You'd have to get a hold of the budget analyst for the department.

D: Do you know who'd be the budget analyst for Thousand Oaks - headquarters? I'm trying to fill out a form and I don't know the proper cost center. P: I just know when y'all need a cost center number, you call your budget analyst. D: Do you have a cost center for your department there in Texas? P: We have our own cost center but they don't give us a complete list of them. D: How many digits is the cost center? FOr example, what's your cost center? P: Well, like, are you with 9WC or with SAT?

Didi had no idea what departments or groups these referred to, but it didn't matter. She answered:

D: 9WC. P: Then it's usually four digits. Who did you say you were with? D: Headquarters--Thousand Oaks. P: Well, here's one for Thousand Oaks. It's 1A5N, that's N like in Nancy.

By just hanging out long enough with somebody willing to be helpful, Didi had the cost center number she needed - one of those pieces of information that no one thinks to protect because it seems like something that couldn't be of any value to an outsider.

The Third Call: A Helpful Wrong Number Didi's next step would be to parlay the cost center number into something of real value by using it as a poker chip.

She began by calling the Real Estate department, pretending she had reached a wrong number. Starting with a "Sorry to bother you, but .... " she claimed she was an employee who had lost her company directory, and asked who you were supposed to call to get a new copy. The man said the print copy was out of date because it was available on the company intranet site.

Didi said she preferred using a hard copy, and the man told her to call Publications, and then, without being asked - maybe just to keep the sexy- sounding lady on the phone a little longer - helpfully looked up the number and gave it to her.

The Fourth Call: Bart in Publications

In Publications, she spoke with a man named Bart. Didi said she was from Thousand Oaks, and they had a new consultant who needed a copy of the company directory. She told him a print copy would work better for the consultant, even if it was somewhat out of date. Bart told her she'd have to fill out a requisition form and send the form over to him.

Didi said she was out of forms and it was a rush, and could Bart be a sweetheart and fill out the form for her? He agreed with a little too much enthusiasm, and Didi gave him the details. For the address of the fictional contractor, she drawled the number of what social engineers call a mail drop, in this case a Mail Boxes Etc.-type of commercial business where her company rented boxes for situations just like this.

The earlier spadework now came in handy: There would be a charge for the cost and shipping of the directory. Fine - Didi gave the cost center for Thousand Oaks:

"IA5N, that's N like in Nancy."

A few days later, when the corporate directory arrived, Didi found it was an even bigger payoff than she had expected: It not only listed the names and phone numbers, but also showed who worked for whom - the corporate structure of the whole organization.

The lady of the husky voice was ready to start making her head-hunter, people- raiding phone calls. She had conned the information she needed to launch her raid using the gift of gab honed to a high polish by every skilled social engineer. Now she was ready for the payoff.

LINGO MAIL DROP: The social engineer's term for a rental mailbox, typically rented under an assumed name, which is used to deliver documents or packages the victim has been duped into sending

MITNICK MESSAGE Just like pieces of a jigsaw puzzle, each piece of information may be irrelevant by itself. However, when the pieces are put together, a clear picture emerges. In this I case, the picture the social engineer saw was the entire internal structure of the company .

Analyzing the Con In this social engineering attack, Didi started by getting phone numbers for three departments in the target company. This was easy, because the numbers she was asking for were no secret, especially to employees. A social engineer learns to sound like an insider, and Didi was skilled at this game. One of the phone numbers led her to a cost center number, which she then used to obtain a copy of the firm's employee directory. The main tools she needed: sounding friendly, using some corporate lingo, and, with the last victim, throwing in a little verbal eyelash-batting. And one more tool, an essential element not easily acquired - the manipulative skills of the social engineer, refined through extensive practice and the unwritten lessons of bygone generations of confidence men.

MORE "WORTHLESS" INFO Besides a cost center number and internal phone extensions, what other seemingly useless information can be extremely valuable to your enemy?.

Peter Abel's Phone Call "Hi," the voice at the other end of the line says. "This is Tom at Parkhurst Travel. Your tickets to San Francisco are ready. Do you want us to deliver them, or do you want to pick them up?" "San Francisco?" Peter says. "I'm not going to San Francisco." "Is this Peter Abels?" "Yes, but I don't have any trips coming up." "Well," the caller says with a friendly laugh, "you sure you don't want to go to

San Francisco?" "If you think you can talk my boss into it..." Peter says, playing along with the

friendly conversation. "Sounds like a mix-up," the caller says. "On our system, we book travel arrangements under the employee number. Maybe somebody used the wrong number. What's your employee number?"

Peter obligingly recites his number. And why not? It goes on just about every personnel form he fills out, lots of people in the company have access to it - human resources, payroll, and, obviously, the outside travel agency. No one treats an employee number like some sort of secret. What difference could it make?

The answer isn't hard to figure out. Two or three pieces of information might be all it takes to mount an effective impersonation - the social engineer cloaking himself in someone else's identity. Get hold of an employee's name, his phone number, his employee number--and maybe, for good measure, his manager's name and phone number--and a halfway- competent social engineer is equipped with most of what he's likely to need to sound authentic to the next target he calls.

If someone who said he was from another department in your company had called yesterday, given a plausible reason, and asked for your employee number, would you have had any reluctance in giving it to him?

And by the way, what is your social security number?

MITNICK MESSAGE The moral of the story is, don't give out any personal or internal company information or identifiers to anyone, unless his or her voice is recognizable and the requestor has a need to know.

PREVENTING THE CON Your company has a responsibility to make employees aware of how a serious mistake can occur from mishandling non public information. A well thought-out information security policy, combined with proper education and training, will dramatically increase employee awareness about the proper handling of corporate business information. A data classification policy will help you to implement proper controls with respect to disclosing information. Without a data classification policy, all internal information must be considered confidential, unless otherwise specified.

Take these steps to protect your company from the release of seemingly innocuous information:

The Information Security Department needs to conduct awareness training detailing the methods used by social engineers. One method, as described above, is to obtain seemingly non sensitive information and use it as a poker chip to gain short-term trust. Each and every employee needs to be aware that when a caller has knowledge about company procedures, lingo, and internal identifiers it does not in any way, shape, or form authenticate the requestor or authorize him or her as having a need to know. A caller could be a former employee or contractor with the requisite insider information. Accordingly, each corporation has a responsibility to determine the appropriate authentication method to be used when employees interact with people they don't recognize in person or over the telephone.

The person or persons with the role and responsibility of drafting a data classification policy should examine the types of details that may be used to gain access for legitimate employees that seem innocuous, but could lead to information that is, sensitive. Though you'd never give out the access codes for your ATM card, would you tell somebody what server you use to develop company software products? Could that information be used by a person pretending to be somebody who has legitimate access to the corporate network?

Sometimes just knowing inside terminology can make the social engineer appear authoritative and knowledgeable. The attacker often relies on this common misconception to dupe his or her victims into compliance. For example, a Merchant ID is an identifier that people in the New Accounts department of a bank casually use every day. But such an identifier exactly the same as a password. If each and every employee understands the nature of this identifier - that it is used to positively authenticate a requestor--they might treat it with more respect.

MITNICK MESSAGE As the old adage goes - even real paranoids probably have enemies. We must assume that every business has its enemies, too - attackers that target the network infrastructure to compromise business secrets. Don't end up being a statistic on computer crime - it's high time to shore up the necessary defenses by implementing proper controls through well-thought-out security policies and procedures.

No companies - well, very few, at least - give out the direct dial phone numbers of their CEO or board chairman. Most companies, though, have no concern about giving out phone numbers to most departments and workgroups in the, organization - especially to someone who is, or appears to be, an employee. A possible countermeasure: Implement a policy that prohibits giving internal phone numbers of employees, contractors, consultants, and temps to outsiders. More importantly, develop a step-by-step procedure to positively identify whether a caller asking for phone numbers is really an employee.

Accounting codes for workgroups and departments, as well as copies of the corporate directory (whether hard copy, data file, or electronic phone book on the intranet) are frequent targets of social engineers. Every company needs a written, well-publicized policy on disclosure of this type of information. The safeguards should include maintaining an audit log that records instances when sensitive information is disclosed to people outside of the company.

Information such as an employee number, by itself, should not be used as any sort of authentication. Every employee must be trained to verify not just the identity of a requestor, but also the requestor's need to know. In your security training, consider teaching employees this approach: Whenever asked a question or asked for a favor by a stranger, learn first to politely decline until the request can be verified. Then - before giving in to the natural desire to be Mr. or Ms. Helpful - follow company policies and procedures with respect to verification and disclosure of non public information. This style may go against our natural tendency to help others, but a little healthy paranoia may be necessary to avoid being the social engineer's next dupe.