A downgrade vulnerability in macOS allows an application to bypass newly added code‑signing restrictions, enabling the app to read or otherwise expose sensitive user data that it should not be able to access. This weakness permits an attacker to retrieve confidential information without the user’s awareness, potentially compromising privacy and integrity of personal or corporate data. The vulnerability aligns with CWE‑200, an information exposure flaw that can lead to unauthorized data disclosure.

Apple macOS systems running any version earlier than macOS Sequoia 15.3, macOS Sonoma 14.7.3, or macOS Ventura 13.7.3 are vulnerable. The issue impacts all Apple Macintosh computers that have not applied the listed security updates.

The CVSS score of 9.8 indicates critical severity, but the EPSS score of less than 1% suggests a very low probability of active exploitation at the time of analysis. This vulnerability is not listed in the CISA KEV catalog. The potential attack vector is a local or user‑directed scenario where the victim runs a malicious application. An adversary would need to deliver or trick the user into installing a downgraded app that bypasses code‑signing checks, after which the app can read protected data. Because no known public exploits are available and exploitation would likely require user interaction, the risk remains moderate to high depending on the environment.