While the security flaw is different from the passcode bug targeted by Tuesday's iOS 6.1.3 update, it results in the same risk -- that of giving unauthorized access to an iPhone's contact list and photos -- tech site said Wednesday.
The process, demonstrated in a YouTube posting by user videosdebarraquito, involves ejecting the phone's SIM card while simultaneously using the iPhone's built-in voice controls to make a phone call, Arstechnica said.
Some web tech sites have been able to recreate the hack on iPhone 4s models, while others have successfully replicated the vulnerability on an iPhone5.
Although voice control seems to be involved, Apple's Siri voice assistant is not creating the vulnerability, but rather Apple's older Voice Control feature, they said.
Apple has not responded to queries about the reported security bug, Arstechnica said.