CVE-2026-84588 in macOS
Summary
by MITRE • 09/15/2026
A memory corruption issue was addressed by removing the vulnerable code. This issue is fixed in macOS Golden Gate 27. Mounting a maliciously crafted disk image may cause unexpected system termination or corrupt kernel memory.
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Analysis
by VulDB Data Team • 09/15/2026
The vulnerability described involves a critical memory corruption flaw within the operating system's handling of disk images, specifically affecting versions prior to macOS Golden Gate 27. This issue stems from improper validation and bounds checking during the parsing or processing of disk image structures in kernel space. When an attacker mounts a maliciously crafted disk image containing specially constructed data patterns, it triggers undefined behavior in the memory management subsystem. The root cause is typically associated with CWE-119 Improper Restriction of Operations within the Bounds of a Memory Buffer or potentially CWE-787 Out-of-bounds Write if the corruption involves overwriting adjacent memory structures. This type of flaw allows for arbitrary code execution, privilege escalation, or denial of service depending on how the corrupted memory is subsequently utilized by the kernel.
The operational impact of this vulnerability is severe due to its location in the kernel space. Kernel memory corruption can lead to immediate system termination, manifesting as a panic or crash, which constitutes a Denial of Service against the affected device. More critically, if an attacker can control the contents written into the corrupted memory regions, they may achieve arbitrary code execution with kernel-level privileges. This bypasses standard user-space security boundaries and allows for full compromise of the system integrity. The ability to corrupt kernel memory undermines fundamental trust mechanisms such as System Integrity Protection (SIP) and secure boot chains, potentially allowing persistent access or stealthy malware installation that is difficult to detect by traditional endpoint protection solutions.
The mitigation strategy employed in macOS Golden Gate 27 involves removing the vulnerable code path entirely rather than patching it with additional checks. This approach eliminates the attack surface associated with processing specific types of disk images that trigger the flaw. By excising the problematic logic, Apple ensures that the conditions necessary for memory corruption cannot be met through this vector. Users are strongly advised to update their systems to macOS Golden Gate 27 or later versions immediately to close this security gap. Until such updates are applied, administrators should restrict the ability of users and applications to mount untrusted disk images, particularly those obtained from external sources or potentially malicious actors.
From a threat intelligence perspective, this vulnerability aligns with ATT&CK techniques related to initial access via compromised software components or supply chain attacks if the disk image is distributed through legitimate channels. It also relates to privilege escalation tactics where kernel exploits are used to gain higher-level permissions after an initial foothold. Security teams should monitor for indicators of compromise that suggest exploitation attempts, such as unusual system crashes following mount operations or unexpected changes in kernel memory states. Continuous monitoring and adherence to strict software supply chain security practices remain essential defenses against the distribution of malicious disk images designed to exploit this class of vulnerabilities.