Subject: ADVISORY: Telephone scam

[ With thanks to Telesis and Bell for providing necessary details. ]

IITS would like to warn the general community at Concordia
about a telephone scam that periodically makes an appearance.


Vulnerability:

  On some business telephone systems, it may be possible for an
  outside caller to gain control of a telephone line and make calls
  charged to that line.

Description:

  This type of fraud involves a perpetrator who calls an office and
  deceives an unsuspecting worker into transferring him or her to an
  outside line by pressing a certain sequence of keys. The perpetrator
  then starts dialing calls that are charged to the owner of the
  telephone line, e.g. Concordia University.

Important notes:

  - The scam does not affect residential customers. It works only on
    business telephone systems which have the appropriate feature set.

  - Though Concordia's telephone system is based on Centrex equipment,
    most of Concordia's telephone lines are not subject to this
    vulnerability. The feature which makes it possible to transfer
    control of a phone line to an outside caller has been turned off
    for most of our telephone lines.

  - Though some of Concordia's telephone lines are vulnerable to this
    scam, the key sequence described in mass e-mail messages which
    circulate periodically differs from that which is required on our
    system.

  - Telephone company service technicians generally do not contact
    customers and request their assistance in testing or repairing
    the telephone lines. You should never press keystrokes you don't
    understand at the request of a stranger.

Suggested action:

  If you suspect that someone is trying to pull such a scam on you, the
  best thing to do is to contact the Concordia switchboard (dial "0")
  and verify the identity of the person calling you. There should never
  be any need to give control of your telephone line to an outside
  caller, and telephone technicians should never need to call and ask
  you to press any sequence of keys.