The new update fixes exploits that could allow hackers to get into the most sensitive parts of the devices.
More worryingly, Apple said that in the case of the three bugs, it “is aware of a report that this issue may have been actively exploited”.
It did not say who was exploiting those vulnerabilities, who may have been hit by them already, how widespread the attacks might be, or any other details on either the perpetrators or victims of the attack.
But it is rare for Apple to publicly say that its devices are not only vulnerable to such an attack but that it was already being exploited by hackers.
It also did not give much particular detail on the vulnerabilities, beyond indicating that they could be used to attack central parts of the phone including the Kernel, which is the very core of the operating system, and the Safari browser.
It notes that access to those fundamental parts of the phone could then be used to escalate to take over the device entirely. Such a technique, known as privilege escalation, is a key way for hackers to attack devices using ostensibly small weaknesses.
Apple’s security pages note that it can evasive or entirely silent about bugs and their fixes until the issue has been solved, to protect the security of its users. “For our customers' protection, Apple doesn't disclose, discuss, or confirm security issues until an investigation has occurred and patches or releases are available," a note on its security update page reads.
The new update is numbered iOS 14.4 and can be downloaded in the usual way, by heading to the Settings app, choosing software update and following the instructions. If it is not done manually, it is likely that all active devices will update themselves soon.
The actual features in the new update are relatively limited. Chief among them is a change that adds an “Important Camera Message” warning when non-Apple hardware is used, to encourage repairs that use genuine cameras.
It also fixes a number of less dangerous bugs, including problems with the keyboard and photos taken on the iPhone 12 Pro.
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