Caller ID spoofing
Encyclopedia
Caller ID spoofing is the practice of causing the telephone network to display a number on the recipient's Caller ID
display
that is not that of the actual originating station. The term is commonly used to describe situations in which the motivation is considered malicious by the speaker or writer. Just as e-mail spoofing
can make it appear that a message came from any e-mail address the sender chooses, Caller ID spoofing can make a call appear to have come from any phone number the caller wishes. Because of the high trust people tend to have in the Caller ID system, spoofing can call the system's value into question.
(PIN), allowing them to make a call for a certain amount of time. To begin, customers dial the number given to them by the company and enter their PIN. Then they enter the number they wish to call and the number they wish to appear as the Caller ID. Once the customer selects these options, the call is bridged or transferred and the person on the other end receives the customer's call. Assuming Caller ID is used on the receiving end, the receiver would normally assume the call was coming from a different phone number — the spoofed number chosen by the caller — thus tricking the receiver into thinking the call was coming from a different individual or organization than the caller's. Most providers work similarly to a prepaid calling card
.
The above method is a bit complex; many Caller ID spoofing service providers also allow customers to initiate spoofed calls from a Web-based interface. Some providers allow entering the name to display along with the spoofed Caller ID number, but in most parts of the United States
, for example, whatever name the local phone company has associated with the spoofed Caller ID number is the name that shows up on the Caller ID display. In other words, the name is not derived from the phone network; instead the originating number is looked up in a database, often over the Internet, and that name is used instead.
Using a Web-based spoofing service involves creating an account with a provider, logging in to their Website and completing a form. Most companies require the following basic fields:
When the user completes this form and clicks a button to initiate the call, the source number is first called. When the source number line is answered, the destination is then called and bridged together.
Some providers also offer the ability to record calls, change the voice and send text messages
.
Other popular methods by companies include displaying only a geographic name on the caller ID readout, e.g., "ARIZONA", "CALIFORNIA", "OREGON", or "ONTARIO".
lines.
Another method of spoofing is that of emulating the Bell 202
FSK
signal. This method, informally called orange box
ing, uses software that generates the audio signal which is then coupled to the telephone line during the call. The object is to deceive the called party into thinking that there is an incoming call waiting
call from the spoofed number, when in fact there is no new incoming call. This technique often also involves an accomplice who may provide a secondary voice to complete the illusion of a call-waiting call. Because the orange box cannot truly spoof incoming caller ID prior to answer and relies to a certain extent on the guile of the caller, it is considered as much a social engineering
technique as a technical hack.
Other methods include switch access to the Signaling System 7 network and social engineering telephone company operators, who place calls for you from the desired phone number.
In the past, Caller ID spoofing required an advanced knowledge of telephony equipment that could be quite expensive. However, with open source software (such as Asterisk
or FreeSWITCH
, and almost any VoIP company), one can spoof calls with minimal costs and effort.
On January 5, 2007, Congressman Engel introduced H.R. 251, and Senator Bill Nelson (D-FL) introduced a similar bill (S.704) two months later. On June 27, 2007, the United States Senate Committee on Commerce, Science and Transportation
approved and submitted to the Senate calendar S.704, a bill that would have made caller ID spoofing a crime. Dubbed the "Truth in Caller ID Act of 2007", the bill would have outlawed causing "any caller identification service to transmit misleading or inaccurate caller identification information" via "any telecommunications service or IP-enabled voice service." Law enforcement was exempted from the rule. Engel's bill passed in the House of Representatives
. Nelson's bill was referred to the same Senate committee that approved S.704. The Senate again passed neither version of the legislation.
In the 111th Congress, Congressman Engel and Senator Nelson once again introduced similar versions of the Caller ID legislation, H.R. 1258. The bill was reintroduced in the Senate on January 7, 2009, as S.30, the Truth in Caller ID Act of 2009, and referred to the same committee The Senate and the House both passed their respective versions of the legislation, but on December 15, 2010 the House passed S.30 and sent the legislation to the President for a signature. On December 22, 2010, President Obama signed the bill into law.
Under the bill, which also targets VOIP services, it becomes illegal "to cause any caller identification service to knowingly transmit misleading or inaccurate caller identification information with the intent to defraud, cause harm, or wrongfully obtain anything of value...." Forfeiture penalties or criminal fines of up to $10,000 per violation (not to exceed $1,000,000) could be imposed. The bill maintains an exemption for blocking one's own outgoing caller ID information, and law enforcement isn't affected.
PRI
circuit. Collection agencies, law-enforcement officials, and private investigators have used the practice, with varying degrees of legality.
The first mainstream Caller ID spoofing service, Star38.com, was launched in September 2004. Star38.com was the first service to allow spoofed calls to be placed from a web interface. It stopped offering service in 2005, as a handful of similar sites were launched.
In August 2006, Paris Hilton
was accused of using caller ID spoofing to break into a voicemail system that used caller ID for authentication. Caller ID spoofing also has been used in purchase scams on web sites such as Craigslist and eBay. The scamming caller claims to be calling from Canada into the U.S. with a legitimate interest in purchasing advertised items. Often the sellers are asked for personal information such as a copy of a registration title, etc., before the (scamming) purchaser invests the time and effort to come see the for-sale items. In the 2010 election, fake caller IDs of ambulance companies and hospitals were used in Missouri to get potential voters to answer the phone. In 2009, a vindictive Brooklyn wife spoofed the doctor’s office of her husband’s lover in an attempt to trick the other woman into taking medication which would make her miscarry.
Frequently, caller ID spoofing is used for prank call
s. For example, someone might call a friend and arrange for "The White House
" to appear on the recipient's caller display. In December 2007, a hacker used a Caller ID spoofing service and was arrested for sending a SWAT
team to a house of an unsuspecting victim. In February 2008, a Collegeville, Pennsylvania
man was arrested for making threatening phone calls to women and having their home numbers appear "on their caller ID to make it look like the call was coming from inside the house." Some companies even feature voice changing and call recording features.
In March 2008, several residents in Wilmington, Delaware
reported receiving telemarketing calls during the early morning hours, when the caller had apparently spoofed the Caller ID to evoke the 1982 Tommy Tutone song 867-5309/Jenny
.
Caller ID
Caller ID , also called calling line identification or calling number identification or Calling Line Identification Presentation , is a telephone service, available in analog and digital phone systems and most Voice over Internet Protocol applications, that transmits a caller's number to...
display
Display device
A display device is an output device for presentation of information in visual or tactile form...
that is not that of the actual originating station. The term is commonly used to describe situations in which the motivation is considered malicious by the speaker or writer. Just as e-mail spoofing
E-mail spoofing
Email spoofing is email activity in which the sender address and other parts of the email header are altered to appear as though the email originated from a different source. Because core SMTP doesn't provide any authentication, it is easy to impersonate and forge emails...
can make it appear that a message came from any e-mail address the sender chooses, Caller ID spoofing can make a call appear to have come from any phone number the caller wishes. Because of the high trust people tend to have in the Caller ID system, spoofing can call the system's value into question.
Providers
To use a typical spoofing service, customers pay in advance for a personal identification numberPersonal identification number
A personal identification number is a secret numeric password shared between a user and a system that can be used to authenticate the user to the system. Typically, the user is required to provide a non-confidential user identifier or token and a confidential PIN to gain access to the system...
(PIN), allowing them to make a call for a certain amount of time. To begin, customers dial the number given to them by the company and enter their PIN. Then they enter the number they wish to call and the number they wish to appear as the Caller ID. Once the customer selects these options, the call is bridged or transferred and the person on the other end receives the customer's call. Assuming Caller ID is used on the receiving end, the receiver would normally assume the call was coming from a different phone number — the spoofed number chosen by the caller — thus tricking the receiver into thinking the call was coming from a different individual or organization than the caller's. Most providers work similarly to a prepaid calling card
Telephone card
A telephone card, calling card or phone card for short, is a small plastic card, sized and shaped like a credit card, used to pay for telephone services. It is not necessary to have the physical card except with a stored-value system; knowledge of the access telephone number to dial and the PIN is...
.
The above method is a bit complex; many Caller ID spoofing service providers also allow customers to initiate spoofed calls from a Web-based interface. Some providers allow entering the name to display along with the spoofed Caller ID number, but in most parts of the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
, for example, whatever name the local phone company has associated with the spoofed Caller ID number is the name that shows up on the Caller ID display. In other words, the name is not derived from the phone network; instead the originating number is looked up in a database, often over the Internet, and that name is used instead.
Using a Web-based spoofing service involves creating an account with a provider, logging in to their Website and completing a form. Most companies require the following basic fields:
- source number
- destination number
- Caller ID number
When the user completes this form and clicks a button to initiate the call, the source number is first called. When the source number line is answered, the destination is then called and bridged together.
Some providers also offer the ability to record calls, change the voice and send text messages
SMS
SMS is a form of text messaging communication on phones and mobile phones. The terms SMS or sms may also refer to:- Computer hardware :...
.
Other popular methods by companies include displaying only a geographic name on the caller ID readout, e.g., "ARIZONA", "CALIFORNIA", "OREGON", or "ONTARIO".
Technology and methods
Caller ID is spoofed through a variety of methods and different technology. The most popular ways of spoofing Caller ID are through the use of VoIP or PRIPrimary rate interface
The Primary Rate Interface is a standardized telecommunications service level within the Integrated Services Digital Network specification for carrying multiple DS0 voice and data transmissions between a network and a user....
lines.
Another method of spoofing is that of emulating the Bell 202
Bell 202 modem
The Bell 202 modem was an early modem developed by Bell System. It specifies audio frequency-shift keying to encode and transfer data at a rate of 1200 bits per second, half-duplex and at a rate of 1800 bits per second full duplex using differential phase-shift keying modulation...
FSK
Frequency-shift keying
Frequency-shift keying is a frequency modulation scheme in which digital information is transmitted through discrete frequency changes of a carrier wave. The simplest FSK is binary FSK . BFSK uses a pair of discrete frequencies to transmit binary information. With this scheme, the "1" is called...
signal. This method, informally called orange box
Orange box
An orange box is a piece of hardware or software that emulates caller ID FSK signals to spoof caller ID information on the target's caller ID terminal. It takes advantage of call waiting caller ID by mimicking the phone company's central office equipment and sending the call waiting tone followed...
ing, uses software that generates the audio signal which is then coupled to the telephone line during the call. The object is to deceive the called party into thinking that there is an incoming call waiting
Call waiting
Call waiting , in telephony, is a feature on some telephone networks. If a calling party places a call to a called party which is otherwise engaged, and the called party has the call waiting feature enabled, the called party is able to suspend the current telephone call and switch to the new...
call from the spoofed number, when in fact there is no new incoming call. This technique often also involves an accomplice who may provide a secondary voice to complete the illusion of a call-waiting call. Because the orange box cannot truly spoof incoming caller ID prior to answer and relies to a certain extent on the guile of the caller, it is considered as much a social engineering
Social engineering (security)
Social engineering is commonly understood to mean the art of manipulating people into performing actions or divulging confidential information...
technique as a technical hack.
Other methods include switch access to the Signaling System 7 network and social engineering telephone company operators, who place calls for you from the desired phone number.
In the past, Caller ID spoofing required an advanced knowledge of telephony equipment that could be quite expensive. However, with open source software (such as Asterisk
Asterisk (PBX)
Asterisk is a software implementation of a telephone private branch exchange ; it was created in 1999 by Mark Spencer of Digium. Like any PBX, it allows attached telephones to make calls to one another, and to connect to other telephone services including the public switched telephone network and...
or FreeSWITCH
Freeswitch
FreeSWITCH is a free and open source communications software for the creation of voice and messaging products. It is licensed under the Mozilla Public License , a free software license...
, and almost any VoIP company), one can spoof calls with minimal costs and effort.
Legislation in the United States
On April 6, 2006, Congressmen Eliot Engel (D-NY) and Joe Barton (R-TX) introduced H.R. 5126, a bill that would have made caller ID spoofing a crime. Dubbed the "Truth in Caller ID Act of 2007", the bill would have outlawed causing "any caller identification service to transmit misleading or inaccurate caller identification information" via "any telecommunications service or IP-enabled voice service." Law enforcement was exempted from the rule. Three weeks later, an identical bill was introduced in the Senate. On June 6, 2006, the House of Representatives passed the Truth in Caller ID Act, although no Senate action was taken on either the House or Senate bill. At the end of the 109th Congress, the bill expired (all pending legislation not voted into law at the end of the House term, a.k.a. end of a session of Congress, is dead).On January 5, 2007, Congressman Engel introduced H.R. 251, and Senator Bill Nelson (D-FL) introduced a similar bill (S.704) two months later. On June 27, 2007, the United States Senate Committee on Commerce, Science and Transportation
United States Senate Committee on Commerce, Science and Transportation
The United States Senate Committee on Commerce, Science, and Transportation is a standing committee of the United States Senate in charge of all senate matters related to the following subjects:* Coast Guard* Coastal zone management* Communications...
approved and submitted to the Senate calendar S.704, a bill that would have made caller ID spoofing a crime. Dubbed the "Truth in Caller ID Act of 2007", the bill would have outlawed causing "any caller identification service to transmit misleading or inaccurate caller identification information" via "any telecommunications service or IP-enabled voice service." Law enforcement was exempted from the rule. Engel's bill passed in the House of Representatives
United States House of Representatives
The United States House of Representatives is one of the two Houses of the United States Congress, the bicameral legislature which also includes the Senate.The composition and powers of the House are established in Article One of the Constitution...
. Nelson's bill was referred to the same Senate committee that approved S.704. The Senate again passed neither version of the legislation.
In the 111th Congress, Congressman Engel and Senator Nelson once again introduced similar versions of the Caller ID legislation, H.R. 1258. The bill was reintroduced in the Senate on January 7, 2009, as S.30, the Truth in Caller ID Act of 2009, and referred to the same committee The Senate and the House both passed their respective versions of the legislation, but on December 15, 2010 the House passed S.30 and sent the legislation to the President for a signature. On December 22, 2010, President Obama signed the bill into law.
Under the bill, which also targets VOIP services, it becomes illegal "to cause any caller identification service to knowingly transmit misleading or inaccurate caller identification information with the intent to defraud, cause harm, or wrongfully obtain anything of value...." Forfeiture penalties or criminal fines of up to $10,000 per violation (not to exceed $1,000,000) could be imposed. The bill maintains an exemption for blocking one's own outgoing caller ID information, and law enforcement isn't affected.
History
Caller ID spoofing has been available for years to people with a specialized digital connection to the telephone company, called an ISDNIntegrated Services Digital Network
Integrated Services Digital Network is a set of communications standards for simultaneous digital transmission of voice, video, data, and other network services over the traditional circuits of the public switched telephone network...
PRI
Primary rate interface
The Primary Rate Interface is a standardized telecommunications service level within the Integrated Services Digital Network specification for carrying multiple DS0 voice and data transmissions between a network and a user....
circuit. Collection agencies, law-enforcement officials, and private investigators have used the practice, with varying degrees of legality.
The first mainstream Caller ID spoofing service, Star38.com, was launched in September 2004. Star38.com was the first service to allow spoofed calls to be placed from a web interface. It stopped offering service in 2005, as a handful of similar sites were launched.
In August 2006, Paris Hilton
Paris Hilton
Paris Whitney Hilton is an American businesswoman, heiress, and socialite. She is a great-granddaughter of Conrad Hilton . Hilton is known for her controversial participation in a sex tape in 2003, and appearance on the television series The Simple Life alongside fellow socialite and childhood...
was accused of using caller ID spoofing to break into a voicemail system that used caller ID for authentication. Caller ID spoofing also has been used in purchase scams on web sites such as Craigslist and eBay. The scamming caller claims to be calling from Canada into the U.S. with a legitimate interest in purchasing advertised items. Often the sellers are asked for personal information such as a copy of a registration title, etc., before the (scamming) purchaser invests the time and effort to come see the for-sale items. In the 2010 election, fake caller IDs of ambulance companies and hospitals were used in Missouri to get potential voters to answer the phone. In 2009, a vindictive Brooklyn wife spoofed the doctor’s office of her husband’s lover in an attempt to trick the other woman into taking medication which would make her miscarry.
Frequently, caller ID spoofing is used for prank call
Prank call
A prank call is a form of practical joke committed over the telephone. Prank phone calls began to gain an America-wide following over a period of many years, as they gradually became a staple of the obscure and amusing cassette tapes traded amongst musicians, sound engineers, and media traders...
s. For example, someone might call a friend and arrange for "The White House
White House
The White House is the official residence and principal workplace of the president of the United States. Located at 1600 Pennsylvania Avenue NW in Washington, D.C., the house was designed by Irish-born James Hoban, and built between 1792 and 1800 of white-painted Aquia sandstone in the Neoclassical...
" to appear on the recipient's caller display. In December 2007, a hacker used a Caller ID spoofing service and was arrested for sending a SWAT
SWAT
A SWAT team is an elite tactical unit in various national law enforcement departments. They are trained to perform high-risk operations that fall outside of the abilities of regular officers...
team to a house of an unsuspecting victim. In February 2008, a Collegeville, Pennsylvania
Collegeville, Pennsylvania
Collegeville is a borough in Montgomery County, Pennsylvania, 30 miles northwest of Philadelphia on the Perkiomen Creek. Collegeville was incorporated in 1896. It is the seat of Ursinus College, opened in 1869...
man was arrested for making threatening phone calls to women and having their home numbers appear "on their caller ID to make it look like the call was coming from inside the house." Some companies even feature voice changing and call recording features.
In March 2008, several residents in Wilmington, Delaware
Wilmington, Delaware
Wilmington is the largest city in the state of Delaware, United States, and is located at the confluence of the Christina River and Brandywine Creek, near where the Christina flows into the Delaware River. It is the county seat of New Castle County and one of the major cities in the Delaware Valley...
reported receiving telemarketing calls during the early morning hours, when the caller had apparently spoofed the Caller ID to evoke the 1982 Tommy Tutone song 867-5309/Jenny
867-5309/Jenny
"867-5309/Jenny" is a song written by Alex Call and Jim Keller and performed by Tommy Tutone that was released on the album Tommy Tutone 2, on the Columbia Records label. It peaked at number four on the Billboard Hot 100 chart and number one on the Billboard Top Tracks chart in 1982...
.
Valid reasons to spoof caller ID
There are legitimate reasons for modifying the caller ID sent with a call.- Calls from a large company, especially with multiple branches, where sending the main number makes sense. For example, a hospital might have the primary number 555-1000, with perhaps 250 lines inside the main building, and another 100 at the clinic five miles away. While some of the phones will have "555-10XX" numbers, many won't have any identifiable line. Having all calls "come from" 555-1000 lets the recipients know it's a hospital call.
- Commercial answering-service bureaus which forward calls back out to a subscriber's cell phone, when both parties would prefer the Caller ID to display the original caller's information.
- Most calling-card companies display the Caller ID of the calling-card user to the called party.
- Business owners have been known to use Caller ID spoofing to display their business number on the Caller ID display when calling from outside the office (for example, on a mobile phone).
- Skype users can assign a Caller ID number in order to prevent their Skype-Out calls being screened by the called party (the default Skype Caller ID in the USA is 0000123456).
- Google VoiceGoogle voiceSearch by voice is a branded name for a technology to "search by voice on your [digital device]", such as a mobile phone or PC, i.e. have the device search for data upon entering information on what to search into the device by speaking....
displays its users' Google Voice number when they place calls through the service using their landline or cell phone. - Gizmo5Gizmo5Gizmo5 was a Voice over Internet Protocol communications network and a proprietary freeware soft phone for that network. On November 12, 2009, Google announced that it had acquired Gizmo5...
sends the user's Gizmo5 SIP number as outbound Caller ID on all calls. Because Gizmo5 IDs are in the format 747NXXXXXX, it is possible to confuse calls made from Gizmo5 with calls made from area code 747Area code 747Area code 747 and area code 818 are California telephone area codes consisting largely of the San Fernando Valley of Los Angeles, California. They cover roughly two million people.-History:...
. - The New York TimesThe New York TimesThe New York Times is an American daily newspaper founded and continuously published in New York City since 1851. The New York Times has won 106 Pulitzer Prizes, the most of any news organization...
sent the number 111-111-1111 for all calls made from its offices until 15 August 2011. The fake number was intended to prevent the extensions of its reporters appearing in call logs, and thus protect reporters from having to divulge calls made to anonymous sources. The Times abandoned this practice because of the proposed changes to the caller ID law, and because many companies were blocking calls from the well-known number.