CVE-2026-43778 in iOS
Summary
by MITRE • 07/28/2026
A use after free issue was addressed with improved memory management. This issue is fixed in iOS 26.6 and iPadOS 26.6, macOS Sequoia 15.7.8, macOS Sonoma 14.8.8, macOS Tahoe 26.6, tvOS 26.6, visionOS 26.6, watchOS 26.6. An app may be able to cause unexpected system termination or corrupt kernel memory.
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Analysis
by VulDB Data Team • 07/28/2026
This vulnerability represents a classic use after free condition that was remediated through enhanced memory management protocols across multiple Apple operating systems. The flaw occurred when an application could manipulate memory allocation patterns in such a way that freed memory blocks were still referenced or accessed by subsequent operations, creating opportunities for system instability and potential exploitation. The issue affected iOS 26.6 and iPadOS 26.6, macOS Sequoia 15.7.8, macOS Sonoma 14.8.8, macOS Tahoe 26.6, tvOS 26.6, visionOS 26.6, and watchOS 26.6, demonstrating the widespread nature of memory management challenges across Apple's ecosystem. The vulnerability classification aligns with CWE-416, which specifically addresses use after free conditions where program memory is accessed after it has been freed by the application or system.
The operational impact of this vulnerability extended beyond simple system crashes to include potential kernel memory corruption that could lead to more severe consequences for system integrity and user data security. When an application triggered the use after free scenario, it could cause unexpected system termination that might result in data loss or service disruption. More critically, the corruption of kernel memory opened possibilities for privilege escalation attacks where malicious code could potentially gain elevated system privileges or manipulate core operating system functions. This type of vulnerability falls under ATT&CK technique T1068, which covers local privilege escalation through exploitation of system vulnerabilities.
The remediation implemented by Apple involved strengthening memory management mechanisms to prevent applications from accessing freed memory blocks after they had been deallocated. These improvements likely included enhanced memory tracking systems, stricter validation of memory access patterns, and additional safeguards within the kernel's memory allocator to ensure that freed resources cannot be reallocated or accessed by other processes. The fix demonstrates Apple's ongoing commitment to addressing memory safety vulnerabilities through comprehensive system-level improvements rather than patching individual applications. Organizations should prioritize updating all affected systems to the patched versions to eliminate exposure to potential exploitation vectors, particularly in environments where untrusted applications might be executed. The vulnerability serves as a reminder of the critical importance of proper memory management practices and the need for continuous security improvements in operating system design.