CVE-2025-43218 is a medium-severity vulnerability affecting Apple macOS, specifically related to the processing of USD (Universal Scene Description) files. The vulnerability arises from an out-of-bounds read condition, classified under CWE-125, which occurs when the system processes a maliciously crafted USD file. This flaw allows an attacker to cause the system to read memory beyond the intended buffer boundaries, potentially disclosing sensitive memory contents. The vulnerability does not allow modification of memory or denial of service but can lead to unauthorized disclosure of information, which could be leveraged for further attacks such as privilege escalation or information gathering. The issue was addressed by Apple through improved input validation in macOS Sequoia 15.6. The CVSS v3.1 base score is 5.5, indicating a medium severity level, with the vector AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N. This means the attack requires local access (AV:L), low attack complexity (AC:L), no privileges required (PR:N), user interaction is needed (UI:R), and the impact is high on confidentiality (C:H), but no impact on integrity (I:N) or availability (A:N). No known exploits are currently reported in the wild. The vulnerability affects unspecified versions of macOS prior to the patch release.

For European organizations, this vulnerability poses a risk primarily to users and systems running vulnerable versions of macOS. Since the attack requires local access and user interaction, the threat vector is limited to scenarios where an attacker can trick a user into opening or processing a malicious USD file, such as via phishing emails, malicious downloads, or compromised removable media. The potential impact includes unauthorized disclosure of sensitive memory contents, which may contain confidential information, credentials, or cryptographic material. This could facilitate further targeted attacks or data breaches. Organizations with macOS endpoints, especially those handling sensitive or regulated data, may face increased risk of information leakage. The impact is more pronounced in sectors with high confidentiality requirements such as finance, healthcare, and government institutions. However, since the vulnerability does not allow remote exploitation without user interaction, the overall risk is moderate but should not be underestimated given the potential for information disclosure.

European organizations should prioritize updating all macOS systems to macOS Sequoia 15.6 or later, where the vulnerability is fixed. In addition to patching, organizations should implement strict endpoint security policies that limit the handling of untrusted USD files, including disabling automatic processing or previewing of such files in email clients and file browsers. User awareness training should emphasize the risks of opening unexpected or suspicious files, particularly USD files received from unverified sources. Employing application whitelisting and restricting local user privileges can reduce the risk of exploitation. Network segmentation and monitoring for unusual file access or execution behaviors related to USD files can help detect potential exploitation attempts. Finally, organizations should maintain up-to-date backups and incident response plans to quickly respond to any compromise.