Overview

• The new protection runs by default on iPhone 17 and iPhone Air, covering the kernel and more than 70 system processes.
• It is built on Enhanced Memory Tagging Extension with tag confidentiality enforcement and secure allocators performing synchronous tag checks.
• Apple claims negligible performance impact and includes a Spectre Variant 1 mitigation, enabled by dedicated A19/A19 Pro silicon resources.
• EMTE tooling ships in Xcode so third-party apps can opt in, though older devices lack the new memory-tagging hardware.
• Researchers welcomed the advance and expect higher exploit costs and disruption for spyware vendors, while noting limits and access concerns for users who cannot upgrade.