More than 128 million iOS users were allegedly affected by the "XcodeGhost" malware which first surfaced in 2015 -- responsible for injecting malware into several iPhone and iPad apps that were subsequently uploaded to the App Store.
Internal Apple emails have revealed during the Epic Games vs Apple trial that 128 million consumers had downloaded more than 2,500 apps infected by the malware that came from the fake copy of Xcode.
In total, these 2,500 infected apps have been downloaded more than 203 million times in the App Store, reports Motherboard.
An employer mentioned that "China represents 55 per cent of customers and 66 per cent of downloads," also referring to the "XcodeGhost" malware.
According to more internal Apple emails, about 18 million affected users were based in the US.
Several developers downloaded the infected Xcode because Apple's servers were slow, so they looked for alternative download links, the report said.
Even popular apps like 'Angry Birds 2' were affected. As soon as the malware was identified, Apple asked developers to immediately recompile their apps with a genuine version of Xcode, it added.
Following this incident, Apple has reinforced both the security of the Xcode installation process and the malware scanning when submitting apps to the App Store.
As the legal battle between Apple and Epic Games began in the US this week, new details emerged, also revealing that Epic Games CEO Tim Sweeney asked Apple CEO Tim Cook to open its iPhones to other app stores as early as 2015.
While Epic Games argues about Apple's monopoly over the app market and treats 30 per cent standard fee amount to anti-competitive behaviour that must be regulated by antitrust law, Apple contends that "the whole antitrust allegation and associated dust-kicking is little more than a PR stunt".
The Fortnite game was removed from App Store in August last year after the company allegedly violated rules by adding an in-game payment system aimed at depriving Apple of its commission on in-app purchases from App Store.