CVE-2026-113903 in iOS
Summary
by MITRE • 10/26/2026
A use-after-free issue was addressed with improved memory management. This issue is fixed in Safari 27.2, iOS 27.2 and iPadOS 27.2, macOS Golden Gate 27.2, visionOS 27.2. Processing maliciously crafted web content may lead to unexpected memory modification.
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 10/27/2026
The vulnerability described constitutes a use-after-free error within the Safari rendering engine and associated WebKit components across iOS, iPadOS, macOS, and visionOS platforms. This class of defect is fundamentally rooted in improper resource management where memory that has been deallocated or freed by the system continues to be referenced by active pointers. In the context of web content processing, this typically occurs when a JavaScript object or DOM element is removed from the document tree but retains references held by event listeners, timers, or asynchronous callbacks. When these lingering references attempt to access the memory location previously occupied by the now-deleted object, they interact with freed heap space rather than valid data structures. This scenario aligns directly with CWE-416, which defines use-after-free as a condition where software uses memory after it has been freed, leading to unpredictable behavior and potential security compromises.
The operational impact of this vulnerability is significant because it allows an attacker who controls the maliciously crafted web content to influence how the browser handles memory operations. By carefully crafting HTML, CSS, or JavaScript payloads that trigger specific race conditions or timing issues during page unload or element removal, a remote user can force the application to write data into arbitrary memory locations. This capability effectively enables arbitrary code execution with the privileges of the current process. In modern mobile and desktop operating systems where browsers operate within sandboxed environments, successfully exploiting this flaw could allow an attacker to escape the browser's security container. Such an escape would grant unauthorized access to sensitive user data, including cookies, local storage contents, and potentially credentials stored by other applications or services running on the device.
From a threat intelligence perspective, this vulnerability maps closely to MITRE ATT&CK technique T1203, which covers exploitation for client execution. Attackers typically deliver such exploits through phishing campaigns, compromised websites, or drive-by download scenarios where users are tricked into visiting a malicious URL. The exploit chain often involves multiple stages, starting with the initial trigger of the use-after-free condition, followed by heap grooming to control the contents of the freed memory block, and finally achieving code execution by overwriting function pointers or object vtables. Because this issue affects core system components like Safari and WebKit on major Apple platforms including visionOS, it represents a high-value target for advanced persistent threats seeking broad access across different device ecosystems without requiring user interaction beyond visiting a webpage.
Apple has addressed this critical flaw in the latest software updates, specifically version 27.2 for Safari, iOS, iPadOS, macOS Golden Gate, and visionOS. The fix involves improved memory management logic within the WebKit engine to ensure that pointers are properly nullified or invalidated immediately after deallocation, preventing any subsequent access attempts from succeeding. To mitigate the risk associated with this vulnerability before applying updates, users should exercise caution when visiting unfamiliar websites or clicking on links received via email or messaging applications. Enabling features such as Intelligent Tracking Prevention and ensuring that browser security settings restrict automatic downloads can reduce the attack surface. However, the most effective mitigation remains prompt installation of the provided software patches to close the memory management gap that allows for arbitrary code execution through malicious web content processing.