CVE-2026-84497 in iOS
Summary
by MITRE • 09/15/2026
A buffer overflow was addressed with improved size validation. This issue is fixed in iOS 26.7 and iPadOS 26.7, iOS 27 and iPadOS 27, macOS Golden Gate 27, macOS Sequoia 15.8, macOS Tahoe 26.7, tvOS 27, visionOS 27. Opening a maliciously crafted file may lead to unexpected process termination.
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Analysis
by VulDB Data Team • 09/15/2026
The vulnerability described constitutes a classic buffer overflow condition within the software components of Apple's operating systems, including iOS, iPadOS, macOS, tvOS, and visionOS. Buffer overflows occur when a program or application writes data beyond the boundaries of a fixed-length memory buffer, potentially overwriting adjacent memory locations. In this specific instance, the root cause is identified as insufficient size validation during file processing operations. When an application attempts to open and parse a maliciously crafted file, it fails to adequately verify that the input data fits within the allocated memory space for the target buffer. This lack of rigorous boundary checking allows external inputs to exceed the intended limits, leading to memory corruption. The technical flaw lies in the failure to implement strict length checks before copying or processing user-supplied data into internal structures, a fundamental security oversight that has been addressed through improved size validation mechanisms in the patched versions.
The operational impact of this vulnerability is primarily characterized by denial of service conditions rather than immediate remote code execution, although the potential for more severe exploitation exists depending on memory layout and exploit techniques employed by attackers. The provided description explicitly states that opening a maliciously crafted file may lead to unexpected process termination. This indicates that the buffer overflow triggers an exception or crash within the affected application, causing it to terminate abruptly. For end-users, this results in service disruption where applications become unresponsive or close unexpectedly upon interacting with specific files. While immediate system compromise is not guaranteed by a simple crash, memory corruption vulnerabilities of this nature are often precursors to more critical exploits if the attacker can control the overwritten data to manipulate return addresses or function pointers. Therefore, even though the observed impact is process termination, the underlying flaw represents a significant security risk that could potentially be leveraged for privilege escalation or arbitrary code execution in unpatched environments where additional mitigations like ASLR and DEP are bypassed or insufficiently configured.
This vulnerability aligns with Common Weakness Enumeration (CWE) category CWE-120, which describes Buffer Copy without Checking Size of Input Classic buffer overflow. It also relates to CWE-20, Improper Input Validation, as the core issue is the failure to validate the size and integrity of incoming data before processing. From a tactical perspective within the MITRE ATT&CK framework, this vulnerability could be associated with techniques involving exploitation for initial access or defense evasion if used in conjunction with other tools to crash security monitoring processes. The attack vector involves local file interaction, meaning an attacker typically needs physical access to the device or social engineering capabilities to trick a user into opening the malicious file locally on their system.
Apple has addressed this issue by implementing improved size validation logic within the affected components across multiple operating systems and versions. The fix ensures that input data is strictly checked against buffer limits before any copy operations occur, thereby preventing memory overwrites. Users are strongly advised to update their devices to iOS 26.7 or iPadOS 26.7, iOS 27 or iPadOS 27, macOS Golden Gate 27, macOS Sequoia 15.8, macOS Tahoe 26.7, tvOS 27, and visionOS 27 as soon as possible to mitigate this risk. Until patches are applied, organizations should enforce strict data handling policies that discourage opening files from untrusted sources and utilize application whitelisting or sandboxing technologies where feasible to limit the impact of potential crashes on critical system functions. Regular security awareness training regarding suspicious file attachments remains a vital complementary defense strategy against such exploitation attempts.