CVE-2026-84546 in iOS
Summary
by MITRE • 09/15/2026
An out-of-bounds write issue was addressed with improved bounds checking. 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, watchOS 27. Processing a maliciously crafted 3D model may lead to memory corruption.
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Analysis
by VulDB Data Team • 09/15/2026
The vulnerability described involves an out-of-bounds write condition within the processing logic for three-dimensional graphics models on Apple operating systems. This type of flaw typically arises when software fails to properly validate the size or boundaries of data structures before writing them into allocated memory regions. In this specific instance, the application responsible for parsing 3D model files did not implement sufficient bounds checking mechanisms. When a maliciously crafted file is processed, it can trigger writes beyond the intended limits of the buffer, leading to heap corruption or stack overflow conditions depending on the internal implementation details of the parser. Such memory corruption issues are critical because they allow an attacker to overwrite adjacent memory locations with arbitrary data, potentially altering program execution flow or corrupting control structures like function pointers and return addresses.
From a technical perspective, this vulnerability aligns closely with CWE-787, which defines out-of-bounds write as accessing memory outside the intended boundary of a buffer. The root cause lies in inadequate input validation where the software assumes that incoming data from external sources will always conform to expected dimensions or lengths without rigorous verification. By processing untrusted 3D model files, an attacker can exploit this lack of validation to execute arbitrary code with the privileges of the affected application. This represents a significant security risk as it bypasses standard memory safety protections and allows for direct manipulation of system resources. The impact extends beyond simple data corruption; successful exploitation could lead to remote code execution, privilege escalation if the vulnerable process runs with elevated permissions, or denial of service through application crashes caused by severe memory instability.
In terms of threat modeling and industry standards, this vulnerability is often associated with ATT&CK technique T1203, which covers Exploitation for Client Execution. Attackers typically deliver malicious 3D files via phishing emails, compromised websites, or file-sharing platforms to trick users into opening them. Once opened by a vulnerable application such as Preview, QuickTime Player, or other graphics-handling software on iOS, iPadOS, macOS, tvOS, visionOS, and watchOS, the exploit payload is activated in memory. The lack of robust bounds checking means that even sophisticated sandboxing mechanisms may be bypassed if the corruption allows for escape from restricted execution environments. This highlights the importance of strict input sanitization and boundary verification in all components responsible for handling complex binary formats like 3D models.
Mitigation strategies primarily involve applying the software updates provided by Apple, which include improved bounds checking logic to prevent writes outside allocated memory regions. Users should ensure their devices are running iOS 26.7 or later, iPadOS 26.7 or later, macOS Golden Gate 27, macOS Sequoia 15.8, macOS Tahoe 26.7, tvOS 27, visionOS 27, and watchOS 27 to benefit from these fixes. Beyond patching, organizations should enforce strict policies regarding the opening of files from untrusted sources and consider deploying application whitelisting or sandboxing solutions that limit the potential impact of such exploits. Regular security audits focusing on memory safety in graphics processing libraries are also recommended to identify similar vulnerabilities before they can be exploited in the wild.