CVE-2025-43326 is a security vulnerability identified in Apple's macOS operating system, specifically addressed in the recent versions macOS Sequoia 15.7, macOS Sonoma 14.8, and macOS Tahoe 26. The vulnerability stems from an out-of-bounds read condition, which occurs when an application reads data outside the boundaries of allocated memory buffers. This type of flaw can lead to unauthorized access to sensitive user data by allowing a malicious or compromised app to read memory regions it should not have access to. The root cause was insufficient bounds checking in the affected macOS components, which Apple has remediated by improving these checks in the patched versions. Although the exact affected macOS versions prior to patching are unspecified, the vulnerability is significant because it potentially compromises the confidentiality of user data on affected systems. No known exploits are currently reported in the wild, and no CVSS score has been assigned yet. However, the nature of the vulnerability—out-of-bounds read leading to sensitive data exposure—indicates a serious security risk, especially given macOS's widespread use in both personal and enterprise environments. The vulnerability does not appear to require user interaction or authentication, meaning that any malicious app installed on the system could exploit this flaw to access sensitive information without additional privileges or user consent.

For European organizations, this vulnerability poses a considerable risk to data confidentiality, especially for sectors handling sensitive or regulated data such as finance, healthcare, legal, and government institutions. The ability of a malicious app to access sensitive user data could lead to data breaches, loss of intellectual property, or exposure of personally identifiable information (PII), potentially violating GDPR and other data protection regulations. Additionally, organizations relying on macOS for critical business operations or development environments may face operational risks if attackers leverage this vulnerability to escalate access or conduct further attacks. The absence of known exploits currently limits immediate risk, but the vulnerability's presence in widely deployed macOS versions means that threat actors could develop exploits in the future, increasing the threat landscape. The impact extends beyond confidentiality to potential reputational damage and financial penalties due to non-compliance with European data protection laws.

European organizations should prioritize updating all macOS devices to the patched versions: macOS Sequoia 15.7, macOS Sonoma 14.8, or macOS Tahoe 26, as soon as possible. Given the unspecified affected versions, organizations should audit their macOS inventory to identify and remediate any unpatched systems. Additionally, organizations should implement strict application control policies to limit the installation and execution of untrusted or unsigned applications, reducing the risk of malicious apps exploiting this vulnerability. Employing endpoint detection and response (EDR) solutions with behavior-based monitoring can help detect anomalous access patterns indicative of exploitation attempts. Regularly reviewing and enforcing least privilege principles on macOS systems will also minimize the potential damage from compromised applications. Finally, organizations should monitor threat intelligence feeds for any emerging exploit reports related to CVE-2025-43326 and adjust their defenses accordingly.