CVE-2024-6222: Docker Desktop Privilege Escalation Flaw

CVE-2024-6222 Overview

CVE-2024-6222 is a container escape vulnerability in Docker Desktop versions prior to v4.29.0. An attacker who has already achieved a container breakout and gained access to the Docker Desktop Virtual Machine can further escalate their access by exploiting weaknesses in the extensions and dashboard-related Inter-Process Communication (IPC) messaging system. This allows the attacker to escape from the VM to the host operating system, compromising the entire host machine.

This vulnerability affects Docker Desktop across multiple operating systems including macOS, Linux, and Windows with Hyper-V backend. The attack chain requires a multi-stage exploitation process, first breaking out of a container into the VM, then leveraging IPC message handling flaws to reach the host system.

Critical Impact

Successful exploitation enables complete host system compromise through container-to-VM-to-host escape chain via malicious IPC messages in Docker Desktop's extension framework.

Affected Products

• Docker Desktop versions before v4.29.0
• Apple macOS systems running vulnerable Docker Desktop versions
• Linux systems running vulnerable Docker Desktop versions
• Microsoft Windows systems (with Hyper-V backend) running vulnerable Docker Desktop versions

Discovery Timeline

• 2024-07-09 - CVE-2024-6222 published to NVD
• 2024-11-21 - Last updated in NVD database

Technical Details for CVE-2024-6222

Vulnerability Analysis

This vulnerability represents a Privilege Escalation and Authorization Bypass flaw in Docker Desktop's IPC communication architecture. The weakness is classified under CWE-923 (Improper Restriction of Communication Channel to Intended Endpoints), indicating that the IPC messaging system fails to properly validate and restrict communication between components.

Docker Desktop uses a layered security model where containers run within a dedicated Virtual Machine, which is intended to provide isolation from the host operating system. The extensions and dashboard functionality rely on IPC messages to communicate between the VM and the host. However, insufficient validation of these IPC messages allows an attacker with VM access to craft malicious messages that can be processed by the host-side components, effectively bypassing the VM boundary.

The exploitation path requires the attacker to first escape from a container into the Docker Desktop VM through a separate container breakout vulnerability. Once inside the VM, the attacker can leverage the IPC messaging weakness to send specially crafted messages that are interpreted by the host system, completing the escape chain.

Root Cause

The root cause is improper restriction of the IPC communication channel used by Docker Desktop's extension and dashboard features. The system fails to adequately authenticate and validate IPC messages originating from within the VM, allowing unauthorized commands to be passed to the host system.

The vulnerability is exacerbated by the default configuration that allowed extensions from sources outside the Docker Marketplace, increasing the attack surface for malicious extension-based attacks.

Attack Vector

The attack requires local access and follows a multi-stage exploitation chain:

1. Initial Container Breakout: The attacker must first compromise a container and escape into the Docker Desktop VM through a separate vulnerability
2. VM-to-Host Escape: From within the VM, the attacker crafts malicious IPC messages targeting the extensions or dashboard communication channels
3. Host Compromise: The malicious IPC messages are processed by host-side components, allowing code execution or other privileged operations on the host system

The attack prerequisites include high privileges and requires user interaction, though the impact extends to complete compromise of confidentiality, integrity, and availability of both the VM and host systems.

Detection Methods for CVE-2024-6222

Indicators of Compromise

• Unusual IPC message activity between Docker Desktop VM and host system
• Unexpected extension installations or modifications outside Docker Marketplace
• Anomalous processes spawned by Docker Desktop host components
• Evidence of container breakout attempts preceding host-level compromise

Detection Strategies

• Monitor Docker Desktop extension installations and verify all extensions are from the official Docker Marketplace
• Implement host-based intrusion detection to identify suspicious processes originating from Docker Desktop components
• Audit IPC communication patterns for anomalous message structures or unexpected endpoints
• Deploy endpoint detection and response (EDR) solutions capable of detecting container escape behavior

Monitoring Recommendations

• Enable Docker Desktop audit logging to capture extension-related activities
• Configure security monitoring for Docker Desktop VM boundary transitions
• Implement file integrity monitoring on Docker Desktop installation directories
• Monitor for privilege escalation attempts following container runtime events

How to Mitigate CVE-2024-6222

Immediate Actions Required

• Upgrade Docker Desktop to version v4.29.0 or later immediately on all macOS, Linux, and Windows (Hyper-V) systems
• For enhanced protection, upgrade to version v4.31.0 which changes the default configuration to only allow Docker Marketplace extensions
• Enable the "Allow only extensions distributed through the Docker Marketplace" setting if using versions between v4.29.0 and v4.31.0
• Audit currently installed extensions and remove any untrusted or unnecessary extensions

Patch Information

Docker has released fixes addressing this vulnerability:

• Docker Desktop v4.29.0: Fixes the IPC message handling vulnerability on macOS, Linux, and Windows with Hyper-V backend. See the Docker Desktop Release Notes v4.29.0 for details.

• Docker Desktop v4.31.0: Additionally changes the default configuration to enable "Allow only extensions distributed through the Docker Marketplace" by default, reducing the attack surface.

Organizations should prioritize upgrading to at least v4.29.0, with v4.31.0 recommended for the additional default security hardening.

Workarounds

• Enable "Allow only extensions distributed through the Docker Marketplace" in Docker Desktop settings to reduce attack surface
• Remove all non-essential Docker extensions until patching is complete
• Implement network segmentation to limit potential lateral movement from compromised containers
• Apply the principle of least privilege to container workloads to reduce initial container breakout risk

# Verify Docker Desktop version
docker version --format '{{.Client.Version}}'

# Check Docker Desktop settings (navigate to Settings > Extensions)
# Ensure "Allow only extensions distributed through the Docker Marketplace" is enabled

# List installed extensions
docker extension ls

# Remove untrusted extensions
docker extension rm <extension-name>