UK bank Barclays was hit by an online security breach Monday morning which allowed at least four customers to access the bank details of other Barclays customers.
The breach follows the introduction of new security infrastructure designed to strengthen the bank's defences Saturday evening and forced the company to close its online services.
According to a Barclays spokeswoman the breach occurred whenever two users attempted to log in at precisely the same moment.
Barclays says the glitch did not become apparent during initial testing and was only uncovered when thousands of users tried to use the service simultaneously. The spokeswoman says no transactions could be executed but in a statement describes the incident in grave terms.
"Barclays views this compromise of the security and integrity of the online services as unacceptable," it reads. "The security of customer information is paramount."
Barclays' online service was taken offline for three hours yesterday afternoon. The new system infrastructure has been replaced by the old and the bank is yet to decide whether it is safe to use.
"The new service will not be re-released until we are satisfied that the particular issue experienced has been rectified," the company says.
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