CVE-2023-38586: Apple macOS Sandbox Bypass Vulnerability

CVE-2023-38586 Overview

CVE-2023-38586 is a critical sandbox bypass vulnerability affecting Apple macOS that allows a sandboxed process to circumvent sandbox restrictions. The vulnerability stems from an access control issue within the macOS sandbox implementation, which Apple addressed by implementing additional sandbox restrictions in macOS Sonoma 14.

The macOS sandbox is a security mechanism designed to contain potentially malicious code by limiting what system resources an application can access. When this containment fails, processes that should be restricted can escape their sandbox boundaries, potentially accessing sensitive system resources, user data, or executing privileged operations that would normally be blocked.

Critical Impact

A sandboxed process can circumvent sandbox restrictions, potentially allowing malicious applications to escape containment and access sensitive system resources or perform unauthorized actions outside their intended security boundary.

Affected Products

• Apple macOS versions prior to macOS Sonoma 14
• apple:macos (all versions before the security update)
• Systems running macOS without the HT213940 security patch applied

Discovery Timeline

• 2023-09-27 - CVE-2023-38586 published to NVD
• 2025-11-04 - Last updated in NVD database

Technical Details for CVE-2023-38586

Vulnerability Analysis

This vulnerability represents a fundamental weakness in the macOS sandbox isolation mechanism. The sandbox is a core security component that enforces the principle of least privilege by restricting what resources and system calls an application can access. When a sandboxed process can circumvent these restrictions, it undermines the entire security model that protects users from malicious or compromised applications.

The scope of this vulnerability extends beyond the vulnerable component itself, meaning successful exploitation can impact resources managed by other security authorities. This cross-boundary impact significantly increases the potential damage from exploitation, as an attacker could leverage a compromised sandboxed application to affect other parts of the system.

The vulnerability requires no user interaction and no privileges to exploit, making it particularly dangerous. An attacker with network access could potentially trigger this vulnerability remotely, allowing complete compromise of confidentiality, integrity, and availability of the affected system.

Root Cause

The root cause of CVE-2023-38586 is an access control issue in the macOS sandbox implementation. While Apple has not disclosed specific technical details about the exact flaw, the vulnerability category (NVD-CWE-noinfo) indicates it relates to improper access control enforcement. The sandbox failed to properly validate or restrict certain operations, allowing sandboxed processes to perform actions outside their permitted scope.

Apple's fix involved adding additional sandbox restrictions, suggesting the original implementation had insufficient boundary checks or missing restrictions for certain system interfaces or resources that could be abused to escape the sandbox containment.

Attack Vector

The attack vector for CVE-2023-38586 is network-based, meaning exploitation can occur remotely without physical access to the target system. An attacker could potentially deliver a malicious payload through:

1. A compromised or malicious application distributed through any channel
2. Web-based attacks targeting sandboxed browser processes
3. Document-based attacks where opening a malicious file triggers code execution within a sandboxed application

Once the malicious code executes within a sandboxed environment, it can exploit this vulnerability to escape the sandbox restrictions and gain access to system resources that should be protected. The low attack complexity and lack of required privileges or user interaction make this vulnerability particularly exploitable.

Since no verified code examples are available for this vulnerability, readers should consult the Apple Security Advisory and Full Disclosure Post for additional technical details about the vulnerability mechanism.

Detection Methods for CVE-2023-38586

Indicators of Compromise

• Unexpected sandbox violation logs or sandbox escape attempts in system.log or unified logging
• Processes attempting to access resources outside their declared sandbox entitlements
• Unusual file system access patterns from applications that should be sandboxed
• System Integrity Protection (SIP) related alerts or bypass attempts

Detection Strategies

• Monitor macOS unified logging for sandbox-related events using log show --predicate 'subsystem == "com.apple.sandbox"'
• Implement endpoint detection rules to identify processes exhibiting behavior inconsistent with their sandbox profile
• Review application entitlements and monitor for runtime entitlement escalation attempts
• Deploy SentinelOne Singularity Platform for real-time behavioral analysis of sandboxed applications

Monitoring Recommendations

• Enable verbose sandbox logging for critical applications and review logs regularly
• Implement network monitoring to detect outbound connections from applications that should have restricted network access
• Utilize Apple's Endpoint Security framework for comprehensive process and file access monitoring
• Configure SentinelOne agents to alert on suspicious sandbox boundary violations and process behavior anomalies

How to Mitigate CVE-2023-38586

Immediate Actions Required

• Upgrade all macOS systems to macOS Sonoma 14 or later immediately
• Verify patch status across all managed Apple devices using MDM solutions or endpoint management tools
• Audit installed applications and remove any untrusted or unnecessary software that could serve as an attack vector
• Enable automatic security updates to ensure timely protection against future vulnerabilities

Patch Information

Apple has addressed this vulnerability in macOS Sonoma 14 by implementing additional sandbox restrictions. The fix is documented in Apple's security advisory HT213940. Organizations should:

1. Download and install macOS Sonoma 14 from the Mac App Store or Apple Software Update
2. For managed environments, deploy the update through MDM solutions such as Jamf, Kandji, or Apple Business Manager
3. Verify successful installation by checking System Settings > General > About and confirming the macOS version is 14.0 or later

Workarounds

• Limit the installation and execution of third-party applications to trusted, verified sources only
• Implement application allowlisting to restrict which applications can run on managed systems
• Use network segmentation to limit potential damage if a sandbox escape occurs
• Consider temporary isolation of critical systems until patches can be applied

# Verify macOS version and patch status
sw_vers -productVersion

# Check for available security updates
softwareupdate --list

# Install all available updates
sudo softwareupdate --install --all --restart