CVE-2025-43218 is a vulnerability in Apple macOS discovered in 2025 that arises from improper input validation when processing USD (Universal Scene Description) files. Specifically, the issue is an out-of-bounds read (CWE-125), which occurs when the system reads memory beyond the intended buffer boundaries while parsing a maliciously crafted USD file. This flaw can lead to the disclosure of sensitive memory contents, potentially leaking confidential information such as cryptographic keys, passwords, or other private data residing in memory. The vulnerability requires local access and user interaction, as an attacker must convince a user to open or process a malicious USD file, which could be delivered via email, removable media, or other file-sharing methods. The CVSS v3.1 score is 5.5 (medium severity), reflecting that the attack vector is local (AV:L), with low attack complexity (AC:L), no privileges required (PR:N), but user interaction is necessary (UI:R). The impact is limited to confidentiality (C:H), with no effect on integrity or availability. Apple addressed this vulnerability by improving input validation in macOS Sequoia 15.6, preventing out-of-bounds reads during USD file processing. No known exploits have been reported in the wild, but the potential for sensitive data leakage warrants timely patching. The vulnerability affects unspecified macOS versions prior to 15.6, so organizations should verify their systems and update accordingly.

For European organizations, this vulnerability poses a risk primarily to confidentiality, as sensitive memory contents could be exposed if a malicious USD file is processed. Sectors such as finance, healthcare, government, and technology that rely on macOS systems and handle sensitive or regulated data are particularly at risk. Although exploitation requires local access and user interaction, targeted phishing or social engineering campaigns could facilitate attacks. The impact is mitigated by the absence of integrity or availability effects, but data leakage could lead to secondary consequences such as credential theft or further compromise. Organizations with macOS endpoints must consider this vulnerability in their risk assessments, especially where USD files are used or exchanged. Failure to patch could expose sensitive internal information, potentially violating data protection regulations like GDPR if personal data is leaked.

1. Apply the macOS Sequoia 15.6 update or later immediately to all affected systems to remediate the vulnerability. 2. Implement strict policies to restrict the opening or processing of USD files from untrusted or unknown sources, including email attachments and removable media. 3. Educate users about the risks of opening unexpected or suspicious files, emphasizing caution with USD files. 4. Deploy endpoint detection and response (EDR) solutions capable of monitoring and alerting on unusual file parsing or memory access patterns associated with USD files. 5. Use application whitelisting to limit execution of unauthorized applications that might process USD files. 6. Conduct regular audits of macOS systems to ensure patches are applied and no unauthorized USD files are present. 7. Consider network segmentation to isolate macOS devices handling sensitive data, reducing the risk of lateral movement if exploited. 8. Monitor threat intelligence sources for any emerging exploit attempts targeting this vulnerability.