The hijacker, Nazamuddin Mohammidy, was part of a group of nine Afghan hijackers who (in 2000) took control, with guns and grenades, of a plane and diverted the flight to Stansted Airport. The hijackers claimed they were fleeing the Taliban.
After the group of hijackers finished their prison time, they all won the right to remain in Britain. And, according to this story, they could do so rent-free and were paid 150,000 a year in British pounds.
Turns out, today, Mohammidy cleans offices and a training center for British Airways. It was a contract position.
Now, I'd wager that, as part of the British Airway's contract with its outsourcer, employees are supposed to be reasonably vetted, including background checks.
This event is the quintessential case study on how contracting and outsourcing pose huge security risks. The only way to possibly protect your organization from this type of situation is to get the list of names of everyone from your contractors and run your own background checks.
Same should be true for any outsourcers given access to applications and sensitive data.
Some people will always slip through, but your net will be much more difficult to get around. And if several people are trying to infiltrate your company, you may only need to nail one to blow the entire plan.
This isn't the first time insiders got to places they shouldn't be in Britain.
So, how does your enterprise vet employees and those of your contractors?