CVE-2026-20630: Apple macOS Information Disclosure Flaw

CVE-2026-20630 Overview

CVE-2026-20630 is a permissions vulnerability in Apple macOS that allows a malicious application to access protected user data. The issue stems from insufficient permission restrictions in the operating system's access control mechanisms. Apple addressed this vulnerability with additional restrictions in macOS Tahoe 26.3.

Critical Impact

A local attacker with low privileges can exploit this vulnerability to gain unauthorized access to protected user data, potentially exposing sensitive information stored on the affected system.

Affected Products

• Apple macOS (versions prior to macOS Tahoe 26.3)

Discovery Timeline

• 2026-02-11 - CVE-2026-20630 published to NVD
• 2026-02-12 - Last updated in NVD database

Technical Details for CVE-2026-20630

Vulnerability Analysis

This vulnerability is classified under CWE-277 (Insecure Inherited Permissions), indicating a flaw in how macOS handles permission inheritance for applications accessing protected user data. The weakness allows an application running with standard user privileges to bypass intended access controls and read sensitive information that should be restricted.

The vulnerability requires local access to the target system and an attacker must be able to execute a malicious application on the affected macOS installation. While the attack complexity is low and no user interaction is required, the scope is contained to the vulnerable component without affecting other system resources. The primary impact is on confidentiality, with no direct effect on system integrity or availability.

Root Cause

The root cause of CVE-2026-20630 lies in improper permission handling within macOS's data protection framework. The operating system failed to enforce adequate restrictions when applications attempted to access protected user data directories and files. This oversight in the permission validation logic allowed applications without proper entitlements to inherit or bypass access controls that should have prevented unauthorized data access.

Attack Vector

The attack vector for this vulnerability is local, requiring an attacker to either have physical access to the target system or the ability to execute code through another mechanism (such as tricking a user into running a malicious application). Once executed, the malicious app can leverage the permissions flaw to access protected user data without proper authorization.

The exploitation scenario involves:

1. An attacker crafts a malicious macOS application designed to exploit the permission weakness
2. The application is executed on a vulnerable macOS system (versions prior to Tahoe 26.3)
3. Due to insufficient permission restrictions, the app bypasses intended access controls
4. Protected user data becomes accessible to the malicious application
5. Sensitive information can be exfiltrated or misused by the attacker

For technical details on the vulnerability mechanism, refer to the Apple Security Advisory.

Detection Methods for CVE-2026-20630

Indicators of Compromise

• Unusual application access to protected user data directories such as ~/Library/Application Support/ or other TCC-protected locations
• Applications without proper entitlements attempting to read sensitive user files
• Unexpected file access events logged by macOS Unified Logging for protected data categories

Detection Strategies

• Monitor macOS Unified Logs for unauthorized attempts to access TCC-protected data categories
• Review installed applications for suspicious or unsigned apps that may be attempting to exploit this vulnerability
• Deploy endpoint detection solutions capable of identifying anomalous file access patterns on macOS systems
• Audit application entitlements to identify apps requesting or accessing data beyond their stated permissions

Monitoring Recommendations

• Enable enhanced logging for file system access events on macOS endpoints
• Implement application allowlisting to prevent execution of unauthorized or untrusted applications
• Configure SentinelOne agents to monitor for suspicious data access patterns and alert on potential exploitation attempts
• Regularly review TCC (Transparency, Consent, and Control) database entries for unexpected permission grants

How to Mitigate CVE-2026-20630

Immediate Actions Required

• Update all affected macOS systems to macOS Tahoe 26.3 or later immediately
• Audit recently installed applications for suspicious behavior or unauthorized data access
• Review application permissions and revoke unnecessary access to protected data categories
• Ensure endpoint protection solutions are updated with the latest detection signatures

Patch Information

Apple has released a security update addressing this vulnerability in macOS Tahoe 26.3. Organizations and users should apply this update as soon as possible to remediate the vulnerability. The official security advisory and update information is available at the Apple Support Article.

Workarounds

• Restrict installation of applications to only trusted sources (Mac App Store or identified developers)
• Implement application control policies to prevent execution of unauthorized software
• Review and limit TCC permissions for installed applications where possible
• Consider isolating sensitive data on systems that cannot be immediately patched

# Check current macOS version to verify patch status
sw_vers -productVersion

# Review TCC database for application permissions (requires Full Disk Access)
sqlite3 ~/Library/Application\ Support/com.apple.TCC/TCC.db "SELECT client,service FROM access"

# List installed applications for audit review
ls -la /Applications/