Technical information

Known Toll Fraud Activity
Issue 7 June 2001
2-7
— Looping
Looping is a method that call sell operators use to circumvent
restrictions that IXCs (Interexchange Carriers) put in the networks to
control calling card fraud. All carriers block calling card calls bound
for the 809 area code (to the Dominican Republic) that originate in
New York, NY. This is because the Dominican Republic is a
common destination for stolen phone calls. If call sell operators are
able to obtain a dial tone from a PBX but are not able to dial 809 or
011 directly, they will revert to looping. They could dial an 800
number outbound from the PBX. The 800 number could be to
another PBX or could be a calling card or operator access number.
Examples include, but are not limited to the following 800 numbers:
1 800 COLLECT, 1 800 CALLATT, and 1 800 GETINFO. They could
also dial 950 carrier access numbers.
Lastly, they can dial various 101xxxx carrier access codes. In any
case, they can still use the PBX to place a fraudulent call. If the PBX
is not in New York, NY, they can use the calling card. Use of the
101xxxx codes could allow for direct billing to the PBX. It is not
uncommon for hackers to “loop” through as many as five
communications systems before completing the fraudulent call.
— Call Diverters
A call diverter is a device used to forward calls to a different location,
usually after business hours. These are normally used for smaller
businesses who forward their calls to an answering service after
hours.
When hackers find a number they suspect is using a call diverter,
they call the number. When the call is answered, the hacker claims
to have misdialed or remains silent. Then when the caller hangs up,
the call diverter sometimes gives the hacker dial tone before the
disconnect is completed. The hacker then seizes the dial tone and
uses it to place fraudulent long distance calls.
— Beeper and/or Pager Scam
A scam directed at pagers and beepers is as follows. Many of the
Local Exchange Carriers (LECs) have run out of numbers in the 976
prefix, so they are using other prefixes that work the same as 976.
That is, the calling party gets charged for the call at a rate set by the
owner of the number.
The fee charged for calling these numbers can range upwards of
$250 per call. As already stated, the fee is set by the owner of the
number. Unscrupulous people who own these numbers call around
the country inserting these numbers into pagers to get the users to
return the call so that they can collect the fee. The 976-look-alike
numbers are constantly changing and expanding. Consult your LEC
for a list of 976-look-alike numbers in your exchange.