CVE-2026-20601 is a security vulnerability identified in Apple macOS, specifically related to a permissions issue that allows an application to monitor keystrokes without obtaining explicit user consent. This vulnerability arises from insufficient enforcement of access control policies governing input monitoring capabilities. The flaw is categorized under CWE-284 (Improper Access Control), indicating that the system failed to properly restrict access to sensitive functionality. The vulnerability affects unspecified versions of macOS prior to the release of macOS Tahoe 26.3, where Apple implemented additional restrictions to address the issue. The CVSS v3.1 base score is 3.3, reflecting a low severity level due to the requirement that the attacker must have local access with some privileges (AV:L, PR:L), no user interaction is needed (UI:N), and the impact is limited to confidentiality (C:L) without affecting integrity or availability. The vulnerability could allow malicious or compromised applications to capture keystrokes, potentially exposing sensitive information such as passwords, personal data, or confidential communications. However, exploitation requires the attacker to have local access and some privileges on the affected system, limiting the attack surface primarily to insider threats or malware that has already gained foothold. No known exploits have been reported in the wild, suggesting limited active exploitation at this time. The fix involves enhanced permission restrictions implemented in macOS Tahoe 26.3, which prevent unauthorized applications from monitoring keyboard input without explicit user authorization.

The primary impact of CVE-2026-20601 is the unauthorized monitoring of keystrokes, which can lead to the exposure of sensitive information such as passwords, personal messages, and confidential data. Although the vulnerability does not affect system integrity or availability, the confidentiality breach can facilitate further attacks like credential theft, espionage, or data leakage. Organizations relying on macOS devices, especially those handling sensitive or regulated data, face increased risk of insider threats or malware leveraging this vulnerability to silently capture user input. The requirement for local privileges reduces the likelihood of remote exploitation but does not eliminate risk from compromised endpoints or malicious insiders. The absence of known exploits in the wild suggests limited immediate threat, but the potential for abuse in targeted attacks remains. Overall, the vulnerability could undermine user privacy and trust, and may have compliance implications for organizations subject to data protection regulations.

To mitigate CVE-2026-20601, organizations should promptly update all macOS devices to version Tahoe 26.3 or later, where the vulnerability has been addressed with enhanced permission restrictions. Additionally, implement strict endpoint security controls to prevent unauthorized local access, including the use of least privilege principles and application whitelisting to limit the installation and execution of untrusted software. Employ monitoring solutions to detect unusual application behavior indicative of input monitoring or keylogging activities. Regularly audit system permissions and review installed applications for suspicious capabilities. Educate users about the risks of installing untrusted software and encourage reporting of unusual system behavior. For high-security environments, consider using hardware-based input protection or multi-factor authentication methods that reduce reliance on keystroke confidentiality. Finally, maintain up-to-date backups and incident response plans to quickly address any compromise.