CVE-2026-20619 Overview
A logging issue in macOS has been identified that fails to properly redact sensitive information. This vulnerability allows applications to potentially access sensitive user data through improper data handling in system logs. Apple has addressed this issue with improved data redaction mechanisms in the affected macOS versions.
Critical Impact
Applications may be able to access sensitive user data due to insufficient log data redaction, potentially exposing private information to malicious or unauthorized apps.
Affected Products
- macOS Sequoia versions prior to 15.7.4
- macOS Tahoe versions prior to 26.3
Discovery Timeline
- 2026-02-11 - CVE-2026-20619 published to NVD
- 2026-02-12 - Last updated in NVD database
Technical Details for CVE-2026-20619
Vulnerability Analysis
This vulnerability stems from inadequate data redaction practices within the macOS logging subsystem. When applications or system processes write log entries, sensitive user data that should be masked or excluded is instead being logged in a retrievable format. This creates an information disclosure risk where other applications with log access permissions could harvest sensitive user information.
The logging infrastructure in macOS is designed to capture diagnostic information while protecting user privacy through data redaction. When this redaction fails, it creates a pathway for sensitive data to be exposed to applications that have legitimate access to read system logs but should not have access to the underlying user data.
Root Cause
The root cause is an Information Exposure vulnerability in the macOS logging mechanism. The system fails to properly redact sensitive user data before writing it to log files, allowing this information to be accessible to applications that can read log entries. This represents a breakdown in the privacy-preserving design of the logging system.
Attack Vector
An attacker could exploit this vulnerability by deploying a malicious application on the target macOS system. Once installed, the application could read system log files to extract sensitive user data that was improperly logged. This attack requires local access and an application to be installed on the victim's system, though social engineering or software supply chain attacks could facilitate deployment.
The exploitation does not require elevated privileges beyond what a standard application might possess for log access. The sensitive data exposure occurs passively as the system continues to log information improperly, allowing ongoing data collection by a malicious app.
Detection Methods for CVE-2026-20619
Indicators of Compromise
- Unusual application behavior involving excessive log file access or parsing
- Applications attempting to access system log directories with high frequency
- Unexpected data exfiltration activity from apps that don't normally require network access after log reads
- Presence of unknown or suspicious applications with log reading capabilities
Detection Strategies
- Monitor for applications making repeated or bulk reads from system log directories
- Implement application allowlisting to prevent unauthorized apps from running
- Review installed applications for any that have been granted unnecessary log access permissions
- Deploy endpoint detection solutions to identify abnormal log access patterns
Monitoring Recommendations
- Enable enhanced logging for file system access to detect log file enumeration
- Configure alerts for applications accessing /var/log or ~/Library/Logs directories excessively
- Monitor network traffic from applications that have recently accessed log files
- Review Gatekeeper and notarization status of all installed applications
How to Mitigate CVE-2026-20619
Immediate Actions Required
- Update macOS Sequoia to version 15.7.4 or later immediately
- Update macOS Tahoe to version 26.3 or later immediately
- Audit installed applications and remove any unnecessary or untrusted software
- Review application permissions, particularly those related to log access
Patch Information
Apple has released security updates that address this vulnerability with improved data redaction:
- macOS Sequoia 15.7.4 - See Apple Security Advisory #126348
- macOS Tahoe 26.3 - See Apple Security Advisory #126349
Users should apply these updates through System Settings > General > Software Update, or through the Mac App Store.
Workarounds
- Limit application installations to only trusted, notarized applications from the App Store
- Enable Gatekeeper to prevent installation of unsigned applications
- Consider using application sandboxing tools to restrict app access to log files
- Regularly review and rotate any credentials that may have been logged prior to patching
- For enterprise environments, consider implementing stricter application control policies until systems can be patched
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
