CVE-2023-38586: Apple macOS Sandbox Bypass Vulnerability

CVE-2023-38586 Overview

CVE-2023-38586 is a sandbox escape vulnerability affecting Apple macOS. Apple addressed the issue by adding additional sandbox restrictions in macOS Sonoma 14. A sandboxed process may circumvent sandbox restrictions and access resources outside its intended security boundary.

The flaw is categorized under [NVD-CWE-noinfo] because Apple did not publicly disclose the specific weakness class. The vulnerability carries a maximum CVSS 3.1 base score, reflecting network attack vector, no privileges required, and a scope change with high impact on confidentiality, integrity, and availability.

Critical Impact
A sandboxed process may break out of its sandbox to access protected resources, undermining a foundational macOS security boundary.

Affected Products

Apple macOS versions prior to macOS Sonoma 14
Systems running unpatched macOS releases on cpe:2.3:o:apple:macos
Applications relying on the macOS App Sandbox for isolation

Discovery Timeline

2023-09-27 - CVE-2023-38586 published to the National Vulnerability Database
2023-09-27 - Apple releases macOS Sonoma 14 security advisory HT213940
2025-11-04 - Last updated in NVD database

Technical Details for CVE-2023-38586

Vulnerability Analysis

The vulnerability allows a sandboxed process on macOS to bypass sandbox restrictions. The macOS App Sandbox enforces fine-grained access controls on file system paths, network endpoints, IPC channels, and system services. A successful bypass lets a process operating inside the sandbox interact with resources that the sandbox profile should block.

Apple's advisory states the issue was addressed with additional sandbox restrictions. This indicates the original policy enforcement allowed an access path that the kernel sandbox extension or sandboxd rules did not block. The patch tightens these rules in macOS Sonoma 14.

The scope change in the CVSS vector reflects the cross-boundary nature of the flaw. Code constrained inside one security authority gains influence over resources managed by another authority on the host.

Root Cause

Apple has not published technical specifics about the underlying defect. Based on the remediation description, the root cause is an incomplete sandbox policy that failed to restrict a specific access vector available to sandboxed processes. The fix introduces additional restrictions rather than altering the sandbox architecture itself.

Attack Vector

Exploitation requires code execution inside a sandboxed process on a vulnerable macOS host. An attacker first delivers malicious code through a sandboxed application such as a browser renderer, mail client, or document viewer. The code then leverages the sandbox bypass to reach resources outside the sandbox profile.

For technical specifics, refer to the Apple Security Advisory HT213940 and the Full Disclosure Mailing List Post.

Detection Methods for CVE-2023-38586

Indicators of Compromise

Sandboxed processes spawning child processes or accessing file paths outside their declared container directories under ~/Library/Containers/
Unexpected XPC connections or Mach service lookups from processes with sandbox_check enforced
macOS Unified Log entries from com.apple.sandbox showing allowed operations that violate expected app behavior

Detection Strategies

Audit Endpoint Security framework events (ES_EVENT_TYPE_NOTIFY_EXEC, ES_EVENT_TYPE_NOTIFY_OPEN) for sandboxed binaries accessing sensitive paths
Monitor for sandboxed applications launching helper processes that escape their container boundary
Correlate process lineage with code signing entitlements to identify behavior inconsistent with the declared sandbox profile

Monitoring Recommendations

Collect Unified Logs from the Sandbox and kernel subsystems for analysis in a centralized logging platform
Track macOS version inventory and flag endpoints running versions earlier than macOS Sonoma 14
Alert on sandboxed processes performing TCC-protected operations such as accessing ~/Library/Mail, Keychain, or Camera APIs

How to Mitigate CVE-2023-38586

Immediate Actions Required

Upgrade all affected systems to macOS Sonoma 14 or later, which contains the additional sandbox restrictions
Inventory macOS endpoints and prioritize patching hosts running browsers, mail clients, and document handlers that rely on sandboxing
Validate that managed configuration profiles enforce automatic security updates through MDM

Patch Information

Apple resolved the issue in macOS Sonoma 14. Patch details are documented in the Apple Security Advisory HT213940. No backport is referenced for earlier macOS major versions in the advisory, so upgrading to Sonoma is the supported remediation path.

Workarounds

Restrict installation of untrusted applications and require notarized, code-signed software via Gatekeeper policy
Enforce least privilege for end-user accounts to limit the impact of a sandbox escape
Disable or remove sandboxed applications that process untrusted input until the host is upgraded

bash

# Verify the installed macOS version meets the patched baseline
sw_vers -productVersion

# Check Apple software update status
sudo softwareupdate --list

# Install all available updates, including macOS Sonoma 14
sudo softwareupdate --install --all --restart