Hackers are believed to have accessed Apple iTunes customer accounts and targeted the book business in particular.
Suspicions were aroused after a seller going by the name of Thuat Nguyen shot up the iTunes book charts, claiming 42 of the top 50 in the sales rankings, Engadget reported.
The books appeared to be illegitimate Vietnamese copies of bestsellers, according to the website, which suggested that the virtual manuscripts could be infringing copyright.
At the time of publication, Apple had not responded to a request from IT PRO for more information on the apparent hack attack.
However, it seems that the Thuat Nguyen books have now been taken down from iTunes.
A number of iTunes users have complained of hackers gaining access to their accounts in recent months. On an Apple discussion board, a post from diw45 dated 27 June claimed that their account was hacked and that purchases made without authorisation came to $240.
Another user, named BridgeRRR, said that $400 worth of purchases had been made on their account without them knowing about it.
"So, just over 2 weeks after 544 was fraudulently spent via my iTunes account, my bank have reimbursed the money to my account," said Crostonblue.
People who have experienced problems such as these can contact Apple Support for more help.
