CVE-2024-40847 is a vulnerability identified in Apple macOS that permits an application to access sensitive user data improperly. The root cause is inadequate enforcement of code-signing restrictions, which normally prevent unauthorized apps from accessing protected data. This vulnerability affects multiple recent macOS versions prior to Sequoia 15, Sonoma 14.7, and Ventura 13.7, where the issue has been fixed. The Common Vulnerability Scoring System (CVSS) rates this flaw at 5.5 (medium severity), with an attack vector requiring local access (AV:L), low attack complexity (AC:L), and privileges required (PR:L), but no user interaction (UI:N). The impact is primarily on confidentiality (C:H), with no impact on integrity or availability. The vulnerability allows an app with limited privileges to bypass protections and read sensitive user data, potentially exposing personal or corporate information. Although no exploits have been observed in the wild, the vulnerability represents a risk for environments where untrusted or malicious apps might be installed or executed. Apple mitigated the issue by implementing stricter code-signing checks to ensure only properly signed and authorized apps can access sensitive data. This fix is included in the latest macOS updates mentioned above.

The primary impact of CVE-2024-40847 is unauthorized disclosure of sensitive user data, which can lead to privacy violations, leakage of confidential corporate information, and potential compliance breaches. Since the vulnerability requires local access and privileges, the risk is higher in environments where users may install untrusted applications or where attackers have gained limited access to a system. The lack of required user interaction lowers the barrier for exploitation once local access is obtained. Although integrity and availability are not affected, the confidentiality breach can facilitate further attacks such as social engineering, identity theft, or targeted espionage. Organizations relying on macOS devices, especially in sectors handling sensitive data like finance, healthcare, and government, may face increased risk if patches are not applied promptly. The absence of known exploits in the wild currently reduces immediate threat but does not eliminate future exploitation possibilities.

To mitigate CVE-2024-40847, organizations should prioritize updating affected macOS systems to Sequoia 15, Sonoma 14.7, or Ventura 13.7 or later versions where the vulnerability is fixed. Beyond patching, organizations should enforce strict application control policies using Apple’s built-in security features such as Gatekeeper and System Integrity Protection (SIP) to restrict installation and execution of untrusted or unsigned applications. Employ endpoint detection and response (EDR) solutions capable of monitoring for suspicious local app behaviors that attempt to access sensitive data. Limit user privileges to the minimum necessary to reduce the risk of privilege escalation and local exploitation. Regularly audit installed applications and remove unnecessary or untrusted software. Educate users about the risks of installing unauthorized apps and the importance of applying system updates promptly. For high-security environments, consider implementing additional data access controls and encryption to protect sensitive information even if accessed by unauthorized apps.