Apple fixes critical font processing bug. Update now!

Apple has released important security updates to address a critical vulnerability in FontParser, the component that processes fonts across MacOS, iOS and iPadOS. The flaw, tracked as CVE-2025-43400, is described as an out-of-bounds write issue that could allow a maliciously crafted font to cause an application's termination or corrupt memory, potentially enabling arbitrary code execution.

While Apple has not stated that it is being actively exploited, similar bugs have been used in jailbreaks and spyware in the past, underscoring the need to patch promptly. Updates for specific devices include iOS 26.0.1 and iPadOS 26.0.1, iOS 18.7.1 and iPadOS 18.7.1, macOS Tahoe 26.0.1, macOS Sequoia 15.7.1, macOS Sonoma 14.8.1, and visionOS 26.0.1, with Apple Watch and Apple TV also receiving respective updates.

The article provides guidance on updating iPhone, iPad, Mac, Apple Watch and Apple TV, emphasising the Software Update or Automatic Updates options and the need to keep devices connected and powered during the process.