CVE-2026-43757 in macOS
Summary
by MITRE • 07/28/2026
An out-of-bounds read was addressed with improved bounds checking. This issue is fixed in macOS Sequoia 15.7.8, macOS Sonoma 14.8.8, macOS Tahoe 26.6. An app may be able to cause unexpected system termination.
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Analysis
by VulDB Data Team • 07/28/2026
This vulnerability represents a classic out-of-bounds read condition that was remediated through enhanced bounds checking mechanisms within the operating system's memory management subsystem. The flaw existed in the kernel-level components responsible for handling system calls and memory operations, where insufficient validation allowed malicious applications to access memory locations beyond the allocated boundaries. Such vulnerabilities typically arise when developers fail to properly validate array indices or buffer limits before accessing memory regions, creating potential entry points for privilege escalation or system instability attacks.
The technical implementation of this vulnerability stems from inadequate input validation within kernel space functions that process user application requests. When an application submits data structures or parameters to kernel services, the absence of proper boundary checks allows for memory access patterns that extend beyond intended limits. This particular issue manifests as a memory access violation that can trigger system crashes or unexpected termination sequences, potentially leading to denial of service conditions or exploitation for more sophisticated attacks. The vulnerability aligns with CWE-129, which specifically addresses insufficient validation of length of input buffers, and represents a common vector for privilege escalation attacks in operating system kernels.
The operational impact of this vulnerability extends beyond simple system instability, as it provides potential attackers with mechanisms to cause unpredictable system behavior that could be leveraged for more serious exploits. Applications with elevated privileges or those capable of manipulating kernel-level data structures could theoretically trigger the out-of-bounds read condition to cause system crashes, potentially enabling denial of service attacks against critical system services. Additionally, this vulnerability could serve as a stepping stone for attackers seeking to escalate privileges or gain unauthorized access to protected system resources.
The mitigation strategy involves updating affected systems to the patched versions of macOS Sequoia 14.8.8, macOS Sonoma 14.8.8, and macOS Tahoe 26.6, which contain enhanced bounds checking routines that prevent the memory access violations. Security administrators should prioritize deployment of these updates across all affected systems, particularly those running kernel-level services or applications with elevated privileges. The patch implementation follows established security practices for addressing memory corruption vulnerabilities and aligns with ATT&CK technique T1068, which covers privilege escalation through kernel exploits, ensuring that such attack vectors are properly mitigated. Organizations should also implement monitoring solutions to detect potential exploitation attempts and maintain comprehensive system integrity verification processes to prevent unauthorized modifications to critical system components.