There are widespread reports that Apple’s Safari web browser is crashing for many users when they carry out a search via its address bar.
Users are complaining that they have experienced the bug on both the firm’s mobile devices and its Mac computers.
Apple recently updated its iOS and OS X operating systems, but users who have not installed the new versions have also reported the fault.
A spokesman for Apple was not able to provide comment.
However, the Verge news site has suggested users disable the “search engine suggestions” option in Safari’s preferences or activate the private mode as a temporary workaround.
However, the current problem appears to be much more widespread, and has been replicated by the BBC.
Apple revealed on Tuesday that there are about one billion of its core devices in use.
The vast majority of those will have been affected, although the number also includes its set-top TV box and smartwatch, which do not use the browser.