CVE-2024-44165: Apple macOS VPN Information Disclosure Flaw

CVE-2024-44165 Overview

CVE-2024-44165 is a logic vulnerability affecting multiple Apple operating systems that allows network traffic to leak outside of a VPN tunnel. This flaw was addressed with improved checks in the affected software. The vulnerability impacts the security and privacy of users who rely on VPN connections to protect their network communications, as sensitive data intended to be encrypted and routed through a secure tunnel may instead be transmitted over unprotected network connections.

Critical Impact

Network traffic may leak outside a VPN tunnel, potentially exposing sensitive user data and communications to network-level attackers, compromising the confidentiality guarantees that VPN users expect.

Affected Products

• Apple macOS (versions prior to Ventura 13.7, Sonoma 14.7, and Sequoia 15)
• Apple iOS and iPadOS (versions prior to 17.7 and 18)
• Apple visionOS (versions prior to 2)

Discovery Timeline

• 2024-09-17 - CVE CVE-2024-44165 published to NVD
• 2025-11-04 - Last updated in NVD database

Technical Details for CVE-2024-44165

Vulnerability Analysis

This vulnerability stems from a logic issue in how Apple's operating systems handle network traffic routing when a VPN connection is active. Under normal circumstances, when a VPN is enabled, all network traffic should be encapsulated and routed through the encrypted VPN tunnel. However, due to improper checks in the network stack, certain traffic may bypass the VPN tunnel entirely and be transmitted directly over the underlying network interface.

The flaw allows confidential information that users intend to keep private through VPN usage to potentially be intercepted by attackers with network access. This is particularly concerning for users in sensitive environments, those using public Wi-Fi networks, or individuals in regions where network surveillance is prevalent. The vulnerability requires no user interaction and can be exploited remotely over the network without any privileges.

Root Cause

The root cause is a logic flaw in the network traffic routing implementation within Apple's operating systems. The system fails to properly enforce that all network traffic must pass through the established VPN tunnel under certain conditions. This allows specific types of network traffic or connections initiated under particular circumstances to bypass the VPN encapsulation, resulting in unprotected data transmission.

Attack Vector

The vulnerability can be exploited over the network by an attacker positioned to observe network traffic (such as on the same network segment or at an ISP level). The attack does not require authentication or user interaction. An attacker could potentially:

1. Monitor network traffic on a shared network (e.g., public Wi-Fi)
2. Identify traffic that leaks outside the VPN tunnel
3. Intercept sensitive data including credentials, browsing activity, or confidential communications
4. Correlate leaked traffic with the user's identity, compromising anonymity

The exploitation relies on the victim having an active VPN connection while the vulnerability causes certain traffic to bypass the tunnel. The attacker does not need to compromise the VPN itself but merely observe traffic on the underlying network.

Detection Methods for CVE-2024-44165

Indicators of Compromise

• Unexpected network traffic originating from device interfaces outside of the established VPN tunnel
• DNS queries being sent to ISP or public DNS servers instead of VPN-configured DNS
• Connection logs showing direct internet-bound traffic while VPN is reported as active
• Network monitoring tools detecting unencrypted traffic from devices expected to use VPN

Detection Strategies

• Implement network traffic analysis to identify traffic patterns that bypass VPN tunnels on managed devices
• Monitor for DNS leaks by comparing DNS query destinations against expected VPN DNS configurations
• Deploy endpoint detection solutions that can identify anomalous network routing behavior
• Review firewall logs for outbound connections that should be routed through VPN but appear on WAN interfaces

Monitoring Recommendations

• Enable verbose logging on network infrastructure to capture detailed traffic flow information
• Implement split-tunnel detection capabilities to identify traffic routing anomalies
• Deploy SentinelOne agents with network visibility features to monitor for VPN bypass conditions
• Establish baseline network behavior profiles for VPN-connected devices to detect deviations

How to Mitigate CVE-2024-44165

Immediate Actions Required

• Update all Apple devices to the patched versions: macOS Ventura 13.7, macOS Sonoma 14.7, macOS Sequoia 15, iOS 17.7, iOS 18, iPadOS 17.7, iPadOS 18, or visionOS 2
• Audit network traffic from Apple devices to identify any potential data exposure
• Consider temporarily avoiding sensitive operations over VPN on unpatched devices
• Notify users of the vulnerability and the importance of applying updates immediately

Patch Information

Apple has released security updates that address this vulnerability with improved logic checks. The following versions contain the fix:

• macOS Ventura 13.7 - Apple Security Update
• macOS Sonoma 14.7 - Apple Security Update
• macOS Sequoia 15 - Apple Security Update
• iOS 17.7 and iPadOS 17.7 - Apple Security Update
• iOS 18 and iPadOS 18 - Apple Security Update
• visionOS 2 - Apple Security Update

Organizations should prioritize deploying these updates through their mobile device management (MDM) solutions.

Workarounds

• Avoid using VPN for sensitive operations on unpatched devices until updates can be applied
• Consider using network-level VPN solutions (such as VPN gateways) rather than device-level VPN clients as a temporary measure
• Implement firewall rules on the network to block non-VPN traffic from known Apple device IP addresses
• Use additional encryption layers (HTTPS, application-level encryption) for sensitive communications

# Verify current macOS version to ensure patch is applied
sw_vers -productVersion

# Check iOS/iPadOS version via command line (if accessible)
# Settings > General > About > Software Version

# Example: Block non-VPN traffic at network firewall for temporary mitigation
# Consult your firewall documentation for specific syntax