CVE-2026-86903 in iPadOS
Summary
by MITRE • 09/15/2026
An out-of-bounds read was addressed with improved input validation. This issue is fixed in iOS 27 and iPadOS 27, macOS Golden Gate 27, tvOS 27, visionOS 27, watchOS 27. An app may be able to disclose kernel memory.
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Analysis
by VulDB Data Team • 09/15/2026
The vulnerability described constitutes a critical out-of-bounds read condition within the operating system's core components, specifically affecting iOS, iPadOS, macOS, tvOS, visionOS, and watchOS versions prior to their respective 27 releases. This flaw arises from insufficient validation of input parameters passed to kernel-level functions, allowing an application to access memory regions that lie outside the intended boundaries of a buffer or data structure. In modern operating systems, particularly those utilizing Apple's secure enclave and strict sandboxing mechanisms, such as iOS and macOS, the kernel maintains tight control over hardware resources and system stability. When input validation is inadequate, the execution flow can be directed to read memory addresses that are not allocated for the specific operation, leading to an out-of-bounds read scenario. This type of error is fundamentally categorized under CWE-125, which defines Out-of-Bounds Read as a weakness where software reads data past the end or before the beginning of the intended buffer.
The operational impact of this vulnerability is significant due to its potential for information disclosure at the kernel level. By exploiting this flaw, a malicious application that has been granted certain privileges or can trigger specific system calls may be able to read sensitive data from the kernel's memory space. This could include cryptographic keys, session tokens, process identifiers, or other confidential information stored in privileged memory regions. The ability of an app to disclose kernel memory undermines the fundamental security model of these operating systems, which relies on strict isolation between user-space applications and the kernel. Such a breach can facilitate further attacks, including privilege escalation or bypassing sandbox restrictions, as the attacker gains insight into internal system states that are normally hidden from unprivileged processes. This aligns with ATT&CK technique T1008, which covers Data from Information Repositories, specifically when applied to memory dumps or direct kernel access for intelligence gathering.
The resolution of this issue involves implementing rigorous input validation checks within the affected components. These improvements ensure that all data inputs are verified against expected bounds before being processed by critical system functions. By validating indices and lengths prior to memory access operations, the operating system prevents any attempt to read from unauthorized memory locations. This fix is deployed across iOS 27, iPadOS 27, macOS Golden Gate 27, tvOS 27, visionOS 27, and watchOS 27, reflecting a comprehensive update strategy that addresses the flaw at its source in the core system libraries. Developers of applications running on these platforms should ensure they are targeting APIs compatible with these updated versions to avoid triggering the vulnerable code paths.
Mitigation strategies for users involve immediate installation of the latest operating system updates provided by Apple. Since this vulnerability allows an app to disclose kernel memory, it represents a high-risk threat that could be exploited in sophisticated attack chains involving zero-day exploits or targeted malware. System administrators and individual users must prioritize patching these platforms to maintain the integrity of their devices. Additionally, adhering to least-privilege principles by restricting application permissions can reduce the surface area for exploitation, although the primary defense remains keeping the operating system up to date with vendor-provided security patches that address such low-level memory safety issues.