CVE-2026-28908 Overview
CVE-2026-28908 is a denial of service vulnerability affecting Apple macOS. The flaw allows an application to modify protected parts of the file system, which can lead to availability impact on affected systems. Apple addressed the issue by removing the vulnerable code in macOS Sequoia 15.7.7, macOS Sonoma 14.8.7, and macOS Tahoe 26.5. The weakness is categorized under [CWE-400] Uncontrolled Resource Consumption. No public exploit is available, and the vulnerability is not listed in the CISA Known Exploited Vulnerabilities catalog.
Critical Impact
An application running on an unpatched macOS system can modify protected file system regions, producing a denial of service condition that affects system availability.
Affected Products
- Apple macOS Sequoia versions prior to 15.7.7
- Apple macOS Sonoma versions prior to 14.8.7
- Apple macOS Tahoe versions prior to 26.5
Discovery Timeline
- 2026-05-11 - CVE-2026-28908 published to NVD
- 2026-05-12 - Last updated in NVD database
Technical Details for CVE-2026-28908
Vulnerability Analysis
The vulnerability resides in macOS file system protection logic. An application can reach code paths that allow modification of protected parts of the file system. Apple's advisory states the issue was addressed by removing the vulnerable code, indicating the affected functionality was non-essential and could be safely eliminated.
The weakness maps to [CWE-400] Uncontrolled Resource Consumption. The CVSS vector indicates the impact is limited to availability, with no confidentiality or integrity loss. Successful exploitation produces a denial of service condition on the local system.
Root Cause
The root cause is improper enforcement of access restrictions on protected file system regions. macOS uses System Integrity Protection (SIP) and related mechanisms to prevent unauthorized modification of critical paths. The affected code permitted an application to bypass these controls and write to areas that should remain immutable. Apple removed the vulnerable code path rather than retrofitting additional checks.
Attack Vector
An attacker delivers a malicious application to the target macOS system. When executed, the application invokes the affected file system interface to alter protected regions. The modification disrupts system services or consumes resources, causing a denial of service. No user interaction beyond running the application is required after initial execution. The vulnerability does not enable remote code execution or data exfiltration.
No verified proof-of-concept code is publicly available. Refer to the Apple Support Article 127115, Apple Support Article 127116, and Apple Support Article 127117 for vendor technical details.
Detection Methods for CVE-2026-28908
Indicators of Compromise
- Unexpected modifications to protected file system paths such as /System, /usr (excluding /usr/local), or other SIP-protected directories.
- Unsigned or untrusted applications invoking file system APIs against restricted locations.
- System service crashes or repeated restarts following execution of a recently installed application.
Detection Strategies
- Monitor endpoint telemetry for processes writing to SIP-protected paths and correlate with code signature validation results.
- Track macOS unified log entries from com.apple.security and file system subsystems for protection violations.
- Apply behavioral analytics to flag applications that probe protected directories shortly after launch.
Monitoring Recommendations
- Establish a baseline of legitimate processes that access privileged file system paths and alert on deviations.
- Forward macOS endpoint logs to a centralized SIEM for retention and correlation across the fleet.
- Track macOS build versions across managed endpoints to identify hosts running vulnerable releases.
How to Mitigate CVE-2026-28908
Immediate Actions Required
- Update affected systems to macOS Sequoia 15.7.7, macOS Sonoma 14.8.7, or macOS Tahoe 26.5 without delay.
- Inventory macOS endpoints to identify hosts running vulnerable builds and prioritize patching.
- Restrict installation of untrusted applications by enforcing Gatekeeper and notarization requirements.
Patch Information
Apple has released fixes in macOS Sequoia 15.7.7, macOS Sonoma 14.8.7, and macOS Tahoe 26.5. Refer to Apple Support Article 127115, Apple Support Article 127116, and Apple Support Article 127117 for the corresponding advisories. The fix removes the vulnerable code path entirely.
Workarounds
- Ensure System Integrity Protection (SIP) is enabled on all macOS endpoints until patches can be deployed.
- Limit user privileges and prevent execution of unsigned applications through managed configuration profiles.
- Use mobile device management (MDM) policies to enforce software update compliance across the fleet.
# Verify macOS version and SIP status
sw_vers -productVersion
csrutil status
# Trigger software update check
sudo softwareupdate --list
sudo softwareupdate --install --all --restart
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
