Apple fixes bug that police used to extract deleted chat messages from iPhones

Apple fixed a bug in a software update for iPhone and iPad where deleted or disappeared messages from messaging apps remained in the notification cache, where they could be read by forensic tools.

• Notifications displaying message content could remain on the device for up to a month, and Apple's security bulletin stated that notifications marked for deletion could unexpectedly persist.
• This pathway was linked to the way deleted Signal messages remained in the device database, allowing law enforcement agencies to read messages that had long since been deleted.
• After this issue was disclosed, Signal asked Apple to fix it, emphasizing that the auto-delete timer feature is important for keeping conversations confidential even in cases of seizure.
• Apple also backported this fix to iPhones and iPads running older versions of iOS 18.

The key point is that even messages deleted within an app cannot be considered completely gone if they remain in the OS-level notification store.