CVE-2023-40452 is a security vulnerability identified in Apple’s iOS, iPadOS, macOS, watchOS, and tvOS platforms. The root cause is an insufficient bounds check in the operating system’s handling of file operations by apps, which allows a malicious application to overwrite arbitrary files on the device. This can lead to unauthorized modification of system or user files, potentially compromising system integrity, causing data loss, or enabling further privilege escalation attacks. The vulnerability affects multiple Apple OS versions prior to the patched releases: macOS Ventura 13.6, macOS Monterey 12.7, macOS Sonoma 14, iOS 17, iPadOS 17, watchOS 10, and tvOS 17. Apple addressed the issue by implementing improved bounds checking to prevent apps from writing outside their authorized file boundaries. No public exploits or active exploitation campaigns have been reported to date, but the nature of the vulnerability means that a malicious app could silently corrupt or replace critical files if the device is compromised. The vulnerability does not require user interaction beyond app installation, and it can be exploited by any app granted installation privileges, making it a significant risk especially in environments where app vetting is less stringent. The lack of a CVSS score necessitates an assessment based on impact and exploitability factors, which indicate a high severity due to the potential for arbitrary file overwrite and the broad scope of affected Apple platforms.

For European organizations, this vulnerability poses a risk to the confidentiality, integrity, and availability of data on Apple devices. The ability for an app to overwrite arbitrary files can lead to system instability, data corruption, or unauthorized modification of critical files, potentially disrupting business operations. Organizations relying on Apple hardware for sensitive communications, data processing, or operational technology could face increased risk of targeted attacks or insider threats exploiting this flaw. The impact is heightened in sectors such as finance, healthcare, government, and critical infrastructure where Apple devices are widely used. Additionally, the vulnerability could be leveraged as a foothold for further attacks, including privilege escalation or persistence mechanisms. The absence of known exploits reduces immediate risk but does not eliminate the threat, especially as attackers often develop exploits post-disclosure. Failure to patch promptly could expose organizations to data integrity issues and compliance risks under European data protection regulations.

European organizations should immediately prioritize updating all Apple devices to the patched OS versions: iOS 17, iPadOS 17, macOS Ventura 13.6, macOS Monterey 12.7, macOS Sonoma 14, watchOS 10, and tvOS 17. Enforce strict app installation policies by limiting app sources to the official Apple App Store and employing Mobile Device Management (MDM) solutions to control app deployment. Conduct regular audits of installed applications to detect unauthorized or suspicious apps. Implement endpoint security solutions capable of monitoring file system changes and alerting on anomalous file overwrite activities. Educate users about the risks of installing untrusted applications and the importance of timely updates. For organizations with sensitive data, consider additional file integrity monitoring and backup strategies to quickly recover from potential file corruption. Finally, maintain vigilance for any emerging exploit reports or indicators of compromise related to this vulnerability.