CVE-2025-43529: Apple Multiple Products Use-After-Free WebKit Vulnerability

Apple products including iOS, iPadOS, and macOS contain a use-after-free vulnerability in the WebKit engine. Processing maliciously crafted web content can trigger memory corruption. The issue affects any HTML parser or renderer that relies on WebKit, such as Safari and third-party applications that embed WebKit components.

How it works

The weakness is classified as CWE-416, a use-after-free condition. In this class of flaw, memory is freed while a pointer to it remains valid. Subsequent operations on that pointer can corrupt memory structures. An attacker supplies specially formed web content that causes WebKit to free an object and later reference the same memory region. The result is memory corruption that may allow arbitrary code execution or application crashes. Specific trigger sequences and exploit mechanics are not detailed in the available summary and must be confirmed against the vendor advisory.

Am I affected? How to find it in your systems

Inventory all devices running Apple iOS, iPadOS, or macOS and any applications that use WebKit for HTML rendering. On managed fleets, query device management platforms for installed operating system versions and browser or app configurations that invoke WebKit. On unmanaged systems, review installed software lists and browser extensions. Non-Apple products that embed WebKit are also in scope. No specific log signatures are provided in the summary; monitor for unexpected process crashes or memory-related errors during web content handling and compare observed behavior against the vendor advisory.

How to remediate

Apply the vendor-supplied update as the primary remediation. Confirm the exact update package and installation steps against the official Apple advisory for each affected product. After patching, review WebKit-dependent configurations and disable unnecessary web content processing features where feasible. Maintain standard hardening practices for browsers and embedded renderers, such as restricting automatic execution of scripts from untrusted sources.

If you can't patch immediately

Follow the CISA directive to apply mitigations per vendor instructions or discontinue use of the affected product if mitigations are unavailable. Segment networks so that devices handling sensitive data have limited exposure to untrusted web content. Consider virtual patching through network filters or web application firewalls that can block or sanitize suspicious HTML and script patterns. Increase monitoring for memory corruption indicators and anomalous WebKit process behavior. Apply applicable BOD 22-01 guidance for any cloud services involved.

If your data may have been exposed

Actively exploited vulnerabilities of this type have led to data breaches in other incidents. Review available telemetry for signs of successful exploitation on affected systems. Organizations can run a free exposure scan of their email domains against known breach data to identify potential prior incidents.