CVE-2026-86902 Overview
CVE-2026-86902 is a path traversal vulnerability [CWE-22] in Apple macOS caused by improper parsing of directory paths. A local application can leverage the flaw to access sensitive user data that should be protected by system access controls. Apple addressed the issue by adding improved path validation in macOS Golden Gate 27 and macOS Sonoma 14.8.8.
The vulnerability requires local access and low privileges but no user interaction. Successful exploitation results in unauthorized disclosure of user data without impacting integrity or availability of the system.
Critical Impact
A malicious or compromised application can bypass directory path checks on macOS to read sensitive user files outside its intended sandbox scope.
Affected Products
- Apple macOS versions prior to Sonoma 14.8.8
- Apple macOS versions prior to Golden Gate 27
- Applications relying on macOS directory path validation for access control
Discovery Timeline
- 2026-09-14 - CVE-2026-86902 published to the National Vulnerability Database
- 2026-09-18 - Last updated in NVD database
Technical Details for CVE-2026-86902
Vulnerability Analysis
The flaw resides in macOS logic that parses and validates directory paths before granting file access. Improper handling of specially crafted path components allows an application to reference locations outside the boundary the operating system intended to enforce. Apple classifies the outcome as unauthorized access to sensitive user data.
Because the attack vector is local, exploitation depends on an attacker already running code on the target system. This includes malware delivered through phishing, malicious installers, or a legitimate app abused as a confused deputy. The vulnerability does not, by itself, grant code execution or persistence.
Root Cause
The root cause is insufficient path canonicalization in directory handling routines, categorized as Improper Limitation of a Pathname to a Restricted Directory [CWE-22]. Path components that resolve outside the allowed base directory were not rejected before file operations proceeded. Apple's fix introduces stricter validation to normalize paths and enforce boundary checks.
Attack Vector
A local, low-privileged process supplies a crafted directory path to an affected macOS API. The parsing routine fails to detect that the resolved path escapes its intended scope. The system then permits the calling process to read files it should not access, exposing sensitive user data such as documents, caches, or per-user configuration.
No verified public exploit is available for CVE-2026-86902. See the Apple security advisories for macOS Sonoma 14.8.8 and macOS Golden Gate 27 for vendor detail.
Detection Methods for CVE-2026-86902
Indicators of Compromise
- Processes issuing file system calls containing ../ sequences or symbolic link chains that resolve outside their working directory
- Non-privileged applications reading files under user home directories they have no legitimate reason to touch, such as ~/Library/Application Support data belonging to other apps
- Unsigned or newly installed applications performing large-scale directory enumeration shortly after launch
Detection Strategies
- Enable Endpoint Security framework auditing for open, openat, and readlink events and alert on path arguments containing traversal sequences
- Baseline normal file access patterns per application bundle identifier and flag deviations that touch other apps' container directories
- Correlate process execution telemetry with file access events to identify applications reading protected paths without an approved entitlement
Monitoring Recommendations
- Forward macOS Unified Log entries related to sandbox violations and TCC prompts to a central SIEM for review
- Monitor for repeated denials followed by successful reads on the same path, which can indicate probing behavior
- Track installation of new applications on managed endpoints and reconcile them against an approved software inventory
How to Mitigate CVE-2026-86902
Immediate Actions Required
- Update all affected Mac endpoints to macOS Sonoma 14.8.8 or macOS Golden Gate 27
- Audit installed applications and remove any that are unsigned, unnecessary, or from untrusted sources
- Restrict installation privileges on managed devices to prevent users from running unvetted software
Patch Information
Apple resolved CVE-2026-86902 by adding improved path validation in macOS Golden Gate 27 and macOS Sonoma 14.8.8. Patch guidance is documented in Apple Support Article 128072 and Apple Support Article 149035. Deploy the updates through Apple software update or an MDM policy that enforces the minimum OS version.
Workarounds
- No vendor-supplied workaround exists; patching is the only supported remediation
- Limit exposure by enforcing Gatekeeper and Notarization requirements to block unsigned applications
- Apply the principle of least privilege for standard user accounts and disable administrator rights where not required
# Verify the installed macOS version meets the patched baseline
sw_vers -productVersion
# Trigger a 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.
