CVE-2026-43665 in macOS
Summary
by MITRE • 07/28/2026
This issue was addressed with additional entitlement checks. This issue is fixed in macOS Sequoia 15.7.8, macOS Sonoma 14.8.8. A local attacker may be able to determine the legacy VNC password configured for Screen Sharing.
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Analysis
by VulDB Data Team • 07/28/2026
This vulnerability represents a privilege escalation and information disclosure flaw affecting Apple macOS systems, specifically targeting the Screen Sharing service configuration mechanisms. The issue stems from insufficient entitlement validation within the system's authentication framework, allowing local attackers to bypass normal access controls and extract sensitive credential information. The vulnerability exists in the legacy VNC password handling mechanism that governs remote desktop access configurations, creating a pathway for unauthorized users to obtain authentication credentials without proper authorization.
The technical implementation flaw resides in the Screen Sharing service's entitlement checking procedures, which fail to properly validate whether local processes have legitimate authorization to access or retrieve legacy VNC password configurations. This weakness enables malicious actors with local system access to exploit insufficient input validation and access control mechanisms that should normally restrict such operations to authorized administrative processes only. The vulnerability specifically affects systems running macOS Sequoia 15.7.8, macOS Sonoma 14.8.8, and potentially other affected versions where the entitlement validation logic remains incomplete.
From an operational impact perspective, this vulnerability creates significant security implications for organizations relying on macOS systems for remote desktop management. Local attackers who can establish a foothold on a system gain access to sensitive authentication credentials that could enable further lateral movement within networks or facilitate more sophisticated attacks. The ability to extract legacy VNC passwords undermines the security posture of systems that depend on these older authentication mechanisms, particularly in enterprise environments where multiple legacy services coexist with modern security controls. This vulnerability aligns with CWE-284 access control weaknesses and represents a direct violation of principle of least privilege.
The mitigation strategy involves implementing the patched versions of macOS operating systems as recommended by Apple's security advisories, which incorporate enhanced entitlement validation procedures for Screen Sharing services. Organizations should also conduct comprehensive system audits to identify any remaining legacy VNC configurations that might still be active within their environments. Additional protective measures include disabling unused screen sharing services, implementing strict access controls for administrative accounts, and monitoring for unauthorized local access attempts. This vulnerability demonstrates the importance of maintaining up-to-date security patches and highlights ATT&CK technique T1078 legitimate credentials usage patterns where attackers exploit system-level authentication mechanisms to gain elevated privileges. The fix addresses the underlying entitlement checking logic that should normally prevent unauthorized access to sensitive service configuration data through proper privilege validation procedures.