CVE-2026-20623 is a permissions-related vulnerability in Apple macOS that permits an application to access protected user data without proper authorization. The root cause is a flaw in the system's permission enforcement, which was resolved by removing the vulnerable code segment in macOS Tahoe 26.3. The vulnerability is classified under CWE-200 (Exposure of Sensitive Information to an Unauthorized Actor), indicating that sensitive data confidentiality is compromised. According to the CVSS 3.1 vector (AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N), exploitation requires local access (AV:L), low attack complexity (AC:L), no privileges (PR:N), and user interaction (UI:R). The scope is unchanged (S:U), and the impact is high on confidentiality (C:H) but none on integrity (I:N) or availability (A:N). No specific affected macOS versions were detailed, but the fix is included in macOS Tahoe 26.3. There are no known exploits in the wild, suggesting limited active exploitation currently. The vulnerability allows unauthorized apps to read sensitive user data, potentially leading to privacy violations or further targeted attacks if combined with other vulnerabilities.

The primary impact of CVE-2026-20623 is the unauthorized disclosure of protected user data on macOS systems. This can lead to privacy breaches, exposure of personal or corporate sensitive information, and potential escalation paths for attackers leveraging the leaked data. Since exploitation requires local access and user interaction, the threat is more relevant to environments where untrusted or malicious applications can be installed or executed by users. Organizations with macOS endpoints, especially those handling sensitive data such as intellectual property, personal identifiable information (PII), or confidential business information, face risks of data leakage. Although the vulnerability does not affect system integrity or availability, the confidentiality breach alone can have regulatory, reputational, and operational consequences. The absence of known exploits in the wild reduces immediate risk but does not eliminate the potential for future exploitation, especially as attackers often develop exploits post-disclosure.

To mitigate CVE-2026-20623 effectively, organizations should: 1) Immediately update all macOS systems to version Tahoe 26.3 or later, where the vulnerable code has been removed. 2) Enforce strict application installation policies, allowing only trusted and verified apps to reduce the risk of malicious apps exploiting this vulnerability. 3) Implement endpoint protection solutions capable of detecting suspicious local activity or unauthorized data access attempts. 4) Educate users about the risks of installing untrusted software and the importance of cautious user interaction, as exploitation requires user action. 5) Regularly audit and monitor macOS systems for unusual access patterns to protected data. 6) Employ macOS security features such as System Integrity Protection (SIP) and privacy controls to limit app permissions. 7) Maintain an inventory of macOS devices and ensure timely patch management processes are in place to rapidly deploy security updates.