CVE-2025-43377 is a security vulnerability identified in Apple macOS, involving an out-of-bounds read condition that arises from inadequate bounds checking within the operating system. This flaw allows a malicious or compromised application to read memory outside the intended buffer boundaries, which can lead to a denial-of-service (DoS) condition by causing the system or affected processes to crash or become unstable. The vulnerability was addressed and fixed in macOS Sequoia 15.7.2 through improved bounds checking mechanisms. The affected versions are unspecified but include macOS versions prior to 15.7.2. No CVSS score has been assigned yet, and there are no known exploits in the wild at the time of publication. The attack vector involves local application execution without the need for user interaction or elevated privileges, making it relatively straightforward for a malicious app to trigger the DoS. The vulnerability impacts system availability by potentially causing system crashes or service interruptions, but does not directly compromise confidentiality or integrity. This type of vulnerability is significant in environments where macOS devices are critical for business operations or service delivery. The fix requires updating to the patched version of macOS, and organizations should monitor for any emerging exploit attempts.

For European organizations, the primary impact of CVE-2025-43377 is on system availability and operational continuity. A successful exploitation could cause macOS devices to crash or become unresponsive, leading to denial-of-service conditions that disrupt workflows, especially in environments relying heavily on Apple hardware such as creative industries, software development, and corporate offices. While the vulnerability does not directly expose sensitive data or allow privilege escalation, the resulting downtime can affect productivity and potentially delay critical business functions. In sectors like finance, healthcare, and government, where uptime and reliability are paramount, such disruptions could have cascading effects. Additionally, organizations with Bring Your Own Device (BYOD) policies that include macOS devices may face increased risk if unpatched devices connect to corporate networks. The absence of known exploits reduces immediate risk but does not eliminate the threat, especially as attackers may develop exploits over time. Therefore, the impact is moderate to high depending on the reliance on macOS systems and the criticality of affected services.

To mitigate the risk posed by CVE-2025-43377, European organizations should prioritize updating all macOS devices to version Sequoia 15.7.2 or later, where the vulnerability is patched. IT departments should enforce strict patch management policies and verify update deployment across all endpoints. Additionally, organizations should restrict the execution of untrusted or unsigned applications through macOS Gatekeeper and implement application whitelisting where feasible to reduce the risk of malicious apps triggering the vulnerability. Network segmentation and endpoint monitoring can help detect anomalous application behavior indicative of exploitation attempts. For environments with sensitive or critical operations, consider limiting macOS device usage to trusted personnel and enforcing strict access controls. Regular security awareness training should include information about the risks of running unverified software. Finally, maintain up-to-date backups and incident response plans to quickly recover from potential denial-of-service incidents.