An application can break out of its sandbox due to improper access control, allowing it to execute code in an unintended environment. The flaw was mitigated by adding stricter sandbox restrictions in macOS Sequoia 15.7.8, Sonoma 14.8.8, and Tahoe 26.6. The weakness corresponds to CWE‑284, Incorrect Access Control.

Apple macOS versions older than Sequoia 15.7.8, Sonoma 14.8.8, and Tahoe 26.6 are vulnerable. Systems running earlier builds of these releases may allow a malicious or compromised application to escape its sandbox and potentially access protected system resources or user data.

The CVSS score of 9.8 marks this vulnerability as critical. An EPSS score of < 1 % and its absence from the CISA KEV catalog suggest that exploitation is currently unlikely, yet the possibility of privilege escalation makes immediate remediation necessary. An attacker would need to deliver or run a malicious application that takes advantage of the insufficient sandbox restriction, potentially via social engineering or by submitting an application signed with a trusted certificate. No publicly disclosed exploits are known, but the high severity warrants rapid patching.