CVE-2026-113943 in macOS
Summary
by MITRE • 10/26/2026
An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in macOS Golden Gate 27.2. Mounting a maliciously crafted disk image may cause unexpected system termination or corrupt kernel memory.
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Analysis
by VulDB Data Team • 10/26/2026
The vulnerability described involves an out-of-bounds write condition within the macOS operating system, specifically affecting components responsible for handling disk images during mounting operations. This type of flaw typically arises when software fails to properly validate input data before writing it to a designated buffer in memory. In this instance, the underlying issue was addressed by implementing improved bounds checking mechanisms, which ensure that any write operation remains within the allocated boundaries of the target memory region. Without such safeguards, an attacker who can induce the system to process a maliciously crafted disk image could trigger a heap or stack overflow, leading to arbitrary code execution with kernel privileges if exploited successfully.
From a technical perspective, out-of-bounds writes are among the most dangerous classes of vulnerabilities because they allow attackers to overwrite adjacent memory structures that may contain critical control data such as function pointers, return addresses, or security cookies. When an attacker crafts a disk image designed to exploit this specific flaw in macOS Golden Gate version 27.2 and prior versions, the system's kernel processes the malformed input without adequate verification of its size relative to the buffer capacity. This lack of validation permits data to spill over into unintended memory locations, potentially corrupting kernel structures or causing immediate system instability. The severity is heightened by the fact that disk image mounting often occurs with elevated privileges, meaning successful exploitation could grant an attacker full control over the operating system core.
The operational impact of this vulnerability includes both denial of service and potential privilege escalation scenarios. As noted in the advisory, attempting to mount a maliciously crafted disk image may cause unexpected system termination, which manifests as a kernel panic or immediate reboot. This represents a significant availability risk for users who rely on continuous uptime for critical tasks. Furthermore, beyond simple crashes, the corruption of kernel memory opens pathways for more sophisticated attacks where an adversary might inject shellcode or manipulate process execution flows to gain unauthorized access to sensitive data or system configurations. Such exploits are particularly concerning in enterprise environments where centralized management and security policies depend heavily on the integrity of the underlying operating system infrastructure.
This vulnerability aligns with Common Weakness Enumeration (CWE) category CWE-787, which defines out-of-bounds write as a memory safety error resulting from writing data beyond the intended boundary of a buffer. It also relates to CWE-120, Buffer Copy without Checking Size of Input, highlighting the fundamental failure in input validation that precedes the actual memory corruption. In terms of tactical mapping within the MITRE ATT&CK framework, this flaw facilitates initial access and privilege escalation techniques commonly associated with local exploitation campaigns. Attackers might leverage social engineering to trick users into opening malicious disk images or exploit network-facing services if such functionality is exposed remotely, thereby bridging external threats with internal system compromise.
Mitigation strategies primarily involve applying the provided software update in macOS Golden Gate 27.2 and later versions, which incorporates the necessary bounds checking improvements developed by Apple engineers. Organizations should prioritize patching endpoints running affected versions to close this attack vector entirely. Additionally, administrators can implement defense-in-depth measures such as enabling kernel integrity protection (KPI) features where available, restricting user permissions for mounting external storage devices, and deploying endpoint detection and response solutions capable of identifying anomalous memory access patterns indicative of exploitation attempts. Regular security audits and adherence to secure coding standards during future development cycles will further reduce the likelihood of similar vulnerabilities emerging in system components responsible for handling untrusted input data from removable media or network sources.