BT bills go open source
By: John Leyden
Posted: 20/04/2001 at 17:26 GMT

Link(active as of 10/22/2006): http://www.theregister.co.uk/content/8/18418.html



BT suspended the services available from its Web site 
for two hours today after an upgrade to its site went 
horribly wrong.

An upgrade to BT's site, which sources suggest involved 
improving security measures for access to customer 
phone bills online,had exactly the opposite effect.

A number of Register readers have written to say that 
when they logged on to access their own bills they were 
able to see other people's bills online.

Mike Bartlett, a press officer at BT, confirmed that 
services were suspended after customers notified the 
telco about securityproblems, which he said had now been 
resolved. BT brought Web- based services back online at 
15:45 UK time today after suspending them at 14:00.

A programming error meant that customer's logging onto 
BT's 'View My Bill' service would see the bill of the 
last person touse the service and not their own, he said.

Bartlett said BT would review its procedures in light of 
today's problems.

BT said the programming error did not mean that it was 
possible to search its database for customer's phone 
records - an assurance that has been questioned by 
security experts.

Paul Rogers, a network security analyst at MIS Corporate 
Defence, said that anyone who registered onto BT's site 
to use the bill viewing feature could see other people's 
phone bills if they knew the customer reference number 
associated with a phone number.

"You don't need to register to view details," said Rogers. 
"The system hasn't been changed to include proper 
authentication and BT are still assuming trust."

Rogers said the problem was similar to an outstanding 
security issue with BT Cellnet's Web site, which made it 
possible to impersonate someone by intercepting or stealing 
a user's session ID.

BT needs to carry out a thorough security review and 
audit, he added.