CVE-2022-42853 is a medium-severity vulnerability affecting Apple macOS, specifically versions prior to macOS Ventura 13.1 where the issue has been addressed. The vulnerability arises from an access control weakness (CWE-284) that allows an application to modify protected parts of the file system. This means that an unprivileged app, potentially without requiring prior authentication (PR:N), but with user interaction (UI:R), could exploit this flaw to alter system files or directories that are normally safeguarded by the operating system's security mechanisms. The CVSS 3.1 vector indicates that the attack requires local access (AV:L), low attack complexity (AC:L), no privileges required, and user interaction is necessary. The impact is primarily on integrity (I:H), with no direct confidentiality or availability impact. The vulnerability does not appear to be exploited in the wild yet, and no public exploits are known. The root cause is an insufficient enforcement of access restrictions, which Apple has fixed in macOS Ventura 13.1 by improving these controls. Given the nature of macOS and its sandboxing, exploitation would likely require the user to run a malicious or compromised app, which then leverages this flaw to escalate its capabilities by modifying protected system files, potentially undermining system stability or security policies.

For European organizations, especially those relying on macOS devices for critical operations, this vulnerability poses a risk to system integrity. An attacker who convinces a user to run a malicious app could modify protected system files, potentially installing persistent backdoors, disabling security features, or corrupting system components. This could lead to compromised endpoints, data manipulation, or further lateral movement within the network. Sectors with high macOS adoption such as creative industries, software development, and certain government or research institutions could be particularly impacted. While the vulnerability does not directly affect confidentiality or availability, the integrity compromise could facilitate more severe attacks. The requirement for local access and user interaction limits remote exploitation but does not eliminate risk, especially in environments where users may install third-party software or are targeted by social engineering. The absence of known exploits in the wild suggests a window for proactive mitigation before widespread abuse occurs.

European organizations should prioritize updating all macOS devices to Ventura 13.1 or later to ensure the patch is applied. Beyond patching, organizations should implement application whitelisting to restrict installation and execution of unauthorized apps, reducing the risk of malicious apps exploiting this vulnerability. Employ endpoint protection solutions capable of monitoring and blocking unauthorized file system modifications, especially in protected directories. User education campaigns should emphasize the risks of installing untrusted software and the importance of verifying app sources. Additionally, leveraging macOS security features such as System Integrity Protection (SIP) and ensuring it is enabled can provide an extra layer of defense. Regular auditing of system files and integrity checks can help detect unauthorized changes early. For organizations with managed devices, enforcing strict device management policies and restricting local user privileges can further reduce exploitation likelihood.