Some owners of the device have complained that the screen of the new iPhone is flickering when the virtual keyboard is displayed.
Users say the issue appeared since the device went on sale in late September.
YouTube videos showing how the display is affected have also been posted online.
In an email to Apple’s senior vice president Scott Forstall, an iDownload Blog reader asked whether the issue was related to software or hardware.
Forstall responded that a software fix is on the way, simply saying: “Thanks. Yes, we have a fix”.
A recent report said that Apple is working on an iOS 6.0.1 update that promises to fix several bugs, including the flickering that appears when the virtual keyboard is displayed.