CVE-2026-64739 in iOS
Summary
by MITRE • 07/28/2026
An out-of-bounds write issue was addressed with improved bounds checking. 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 attacker may be able to cause unexpected app termination.
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Analysis
by VulDB Data Team • 07/28/2026
This vulnerability represents a classic out-of-bounds write condition that was remediated through enhanced bounds validation mechanisms within Apple's operating systems. The flaw existed in the underlying memory management and array handling routines where insufficient boundary checks allowed malicious code to write data beyond allocated memory regions. Such issues typically arise when developers fail to properly validate input parameters or array indices before performing memory operations, creating opportunities for buffer overflows that can be exploited by attackers to manipulate program execution flow.
The technical implementation of this vulnerability aligns with common software security weaknesses documented in CWE-129, which specifically addresses insufficient bounds checking on entries to a resource. The flaw likely manifested in kernel-level or system framework components where memory allocations occur without proper validation of input parameters that determine array boundaries. This type of vulnerability is particularly concerning because it can be leveraged to cause arbitrary code execution or system instability when an attacker successfully manipulates the bounds checking logic to write beyond intended memory segments.
The operational impact of this vulnerability extends beyond simple application crashes, as demonstrated by the potential for unexpected app termination across multiple Apple platforms including iOS, iPadOS, macOS variants, tvOS, visionOS, and watchOS. Attackers could potentially exploit this condition to trigger denial-of-service scenarios or in more sophisticated attacks, manipulate system memory to execute malicious payloads. The vulnerability affects a broad range of devices and operating system versions, indicating it was likely present in core system libraries rather than specific applications, making the exploitation surface particularly wide-reaching.
The remediation implemented by Apple through version updates addresses this issue by strengthening the bounds checking mechanisms throughout the affected operating systems. The fixes typically involve enhanced input validation routines that verify array indices and memory access parameters before allowing write operations to proceed. These patches would have been integrated into system frameworks such as CoreFoundation, Foundation, or similar kernel components where memory management occurs. The coordinated release across multiple platform versions demonstrates Apple's approach to addressing critical security issues through systematic patch management rather than platform-specific fixes.
Security professionals should consider this vulnerability in relation to ATT&CK framework techniques that involve privilege escalation and code execution through memory corruption. The out-of-bounds write condition could potentially be chained with other vulnerabilities to achieve more sophisticated exploitation objectives, making it a critical component in threat modeling for enterprise environments. Organizations should prioritize patching these systems to prevent potential exploitation by threat actors who may be actively targeting these specific versions of Apple operating systems.
The vulnerability highlights the ongoing challenges in modern software development where complex memory management systems must balance performance requirements with security robustness. The fact that this issue required bounds checking improvements indicates that the original implementation had insufficient validation of memory access patterns, particularly in scenarios involving user input or external data processing within system frameworks. This aligns with common attack patterns observed in zero-day exploits targeting mobile and desktop operating systems where attackers seek to leverage memory corruption vulnerabilities for persistent access to target systems.
The patching strategy employed by Apple demonstrates industry best practices for managing critical vulnerabilities through coordinated releases, ensuring that all affected platforms receive consistent security updates. The multi-platform approach to addressing this issue reflects the interconnected nature of modern computing environments where vulnerabilities in one component can affect multiple operating system variants. This vulnerability serves as a reminder of the importance of maintaining up-to-date security patches across all system components and highlights the critical role that automated patch management plays in enterprise security operations.