CVE-2025-43464 is a denial-of-service (DoS) vulnerability in Apple macOS caused by improper input validation (CWE-20). When a user visits a specially crafted malicious website, the vulnerability can be triggered, causing an application on macOS to crash or become unresponsive, thereby denying service to the user. The vulnerability affects unspecified versions of macOS prior to the release of macOS Tahoe 26.1, which contains the fix. The CVSS v3.1 base score is 6.5, indicating medium severity, with the vector AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H. This means the attack can be launched remotely over the network without privileges but requires user interaction (visiting a malicious website). The scope remains unchanged, and the impact is limited to availability, with no confidentiality or integrity impact. The root cause is insufficient input validation, which Apple addressed by improving validation mechanisms in the patched version. There are no known exploits in the wild at this time, but the vulnerability poses a risk of service disruption, especially in environments where macOS applications are critical. Since the vulnerability is triggered by web content, it could be exploited via phishing or malicious advertising campaigns. The lack of a patch link in the provided data suggests users should upgrade to macOS Tahoe 26.1 as soon as it becomes available to mitigate this risk.

For European organizations, the primary impact of CVE-2025-43464 is the potential disruption of business operations due to denial-of-service conditions on macOS devices. This can affect productivity, especially in sectors relying heavily on Apple hardware and software, such as creative industries, software development, and certain government agencies. Although the vulnerability does not compromise data confidentiality or integrity, the availability impact can lead to downtime, loss of user trust, and increased support costs. Organizations with remote or hybrid workforces using macOS devices are particularly vulnerable if users access malicious websites unknowingly. Additionally, critical infrastructure or services running on macOS could face interruptions, which may have cascading effects. The absence of known exploits reduces immediate risk but does not eliminate the threat, as attackers could develop exploits once the vulnerability details are public. The reliance on user interaction means social engineering campaigns could be used to increase exploitation likelihood.

1. Upgrade all macOS devices to macOS Tahoe 26.1 or later immediately upon release to ensure the vulnerability is patched. 2. Implement web filtering and DNS filtering solutions to block access to known malicious websites and reduce the risk of users visiting harmful content. 3. Educate users about the risks of visiting untrusted websites and the importance of cautious browsing behavior, especially avoiding links from unknown or suspicious sources. 4. Deploy endpoint protection solutions capable of detecting abnormal application behavior indicative of denial-of-service conditions. 5. Monitor network traffic and application logs for signs of repeated crashes or unresponsiveness that may indicate exploitation attempts. 6. For organizations with critical macOS applications, consider isolating these systems or restricting web access until patches are applied. 7. Maintain an up-to-date inventory of macOS devices to ensure timely patch management and vulnerability tracking. 8. Coordinate with IT and security teams to develop incident response plans specific to denial-of-service events on macOS platforms.