Account hijackers have targeted Apple iTunes for months, but now they're hitting Apple developers as well.

Reg reader Andrew McAuley discovered that his iTunes account was hijacked after 150 unauthorised transactions, each valued at $42, appeared on his debit card bill. McAuley, a Brit who lives in the US, noticed the attack after he checked his bank account on 11 July. "I tried to log in to my [iTunes] account and was unable. Seems someone had changed the login to a different name completely," he explained.

When he contacted iTunes support McAuley was told his account had been taken over by an "unknown fraudster" and that this was the subject of an ongoing investigation. Apple has suspended the account.

McAuley didn't suffer financially because his debit card was protected by a $0 liability guarantee. He doesn't store any card details on his UK account, which isn't covered by an equivalent indemnity. In the UK, credit card holders are only liable to the first £50 of any purchase. But despite not losing out financially McAuley is concerned about the hijack.

Andrew Goodwill, director of credit card fraud protection specialist The 3rd Man, suggested that payment card details, obtained elsewhere, were used to make the purchases on our reader's account. "They will get card details in the normal way (not from iTunes) and use them to download music. It's just normal credit card fraud," Goodwill said. "iTunes need a better anti-fraud system," he added.

McAuley disputed this finding, pointing to complaints from more victims of iTunes account hacking over several months on various support forums. A common pattern emerges (examples here and here).

Perpetrators typically change the email address associated with an account to one under their control, typically a webmail account that can easily be established without any identity checks. They also change the password. Sometimes, but not always, they change the billing address and telephone number associated with an account. Once compromised, accounts are used to make multiple purchases of relatively high value, typically around $40.

Apple has not replied to our request for clarification on what iTunes support staff are calling an ongoing investigation into account hijacking. The company is also keeping schtum on what customers should do if they suspect their iTunes account has been misused to make fraudulent purchases.

McAuley warns against associating debit or credit card payment details with iTunes accounts, advice also frequently given on bulletin boards. The inconvenience of having to enter payment details each time a purchase is made seems like a small price to pay for security.

Pass the password

Some Apple developers have also been stung by similar hijacking attacks in recent weeks. Marko Karppinen was locked out of his Apple Developer Connection account earlier this month after his password and registered email address were both changed without his authorisation. Karppinen said that Apple emailed a reset password to a Yahoo email address not under his control after someone sent a one-line email full of grammatical errors to support staffers via a web support form.

The hijacker entered Karppinen's Apple ID in the email field, and as a result Karppinen received a copy of Apple's response in his .Mac mailbox.

"Luckily, my 'security question' was still the same, so I was able to reset the password and email address back," Karppinen said.

A representative of Apple Developer Connection's European support organisation has since been in touch with Karppinen to apologise and assure him that passwords are not normally handed out so readily.

Alec Muffett, a network security expert, responded to Karppinen's tale by posting links to accounts of his own experiences of suffering from credit card fraud days after his Apple ID was stolen in November 2006. Although he has no proof Muffett reckons this is more than just a coincidence. He reckons that crooks either got the credit card number from Apple, or swiped info from his Apple account to fill gaps in information they had obtained somewhere else.

"My theory is that the crooks are milking Apple IDs - with their oh-so-friendly password recovery mechanism - for card meta-information, correlating it with stuff elsewhere, and then using it on the handful of traders who’ll accept dubious data for anonymous services," Muffett wrote.

Muffett's blog contains tips on how to avoid getting hit.

"If Apple are going to [run] MobileMe off the same system, it would make sense to beef this security up," he adds. ®