CVE-2025-43359
📋 TL;DR
This CVE describes a UDP socket binding vulnerability in Apple operating systems where a UDP server socket bound to a local interface may unexpectedly become bound to all interfaces. This affects multiple Apple platforms including iOS, macOS, tvOS, watchOS, and visionOS, potentially allowing unauthorized network access.
💻 Affected Systems
- iOS
- iPadOS
- macOS
- tvOS
- watchOS
- visionOS
📦 What is this software?
Ipados by Apple
Macos by Apple
macOS is Apple's desktop and laptop operating system powering Mac computers used by millions of professionals, developers, creative professionals, and enterprise users worldwide. Built on a Unix foundation with the Darwin kernel and modern Cocoa frameworks, macOS delivers a seamless ecosystem integr...
Learn more about Macos →Macos by Apple
macOS is Apple's desktop and laptop operating system powering Mac computers used by millions of professionals, developers, creative professionals, and enterprise users worldwide. Built on a Unix foundation with the Darwin kernel and modern Cocoa frameworks, macOS delivers a seamless ecosystem integr...
Learn more about Macos →Tvos by Apple
Watchos by Apple
⚠️ Risk & Real-World Impact
Worst Case
An attacker could intercept or inject UDP traffic intended for local services, potentially leading to data exfiltration, service disruption, or lateral movement within the network.
Likely Case
Unauthorized network access to UDP services that should be restricted to local interfaces, potentially exposing sensitive services to network attacks.
If Mitigated
With proper network segmentation and firewall rules, the impact is limited to potential information disclosure about UDP service availability.
🎯 Exploit Status
Exploitation requires knowledge of UDP services running on affected systems and the ability to send network traffic to those systems.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: tvOS 26, watchOS 26, macOS Sonoma 14.8, iOS 26 and iPadOS 26, macOS Sequoia 15.7, visionOS 26, iOS 18.7 and iPadOS 18.7
Vendor Advisory: https://support.apple.com/en-us/125108
Restart Required: Yes
Instructions:
1. Go to Settings > General > Software Update on iOS/iPadOS/tvOS/watchOS/visionOS. 2. Install the latest available update. 3. For macOS, go to System Settings > General > Software Update and install the latest update. 4. Restart the device after installation.
🔧 Temporary Workarounds
Network Segmentation
allImplement strict network segmentation to isolate affected devices and restrict UDP traffic flow
Firewall Rules
allConfigure host-based or network firewalls to block unauthorized UDP traffic to potentially affected ports
🧯 If You Can't Patch
- Implement strict network segmentation to isolate affected Apple devices from sensitive network segments
- Deploy host-based firewalls on affected devices to restrict UDP traffic to only necessary sources and destinations
🔍 How to Verify
Check if Vulnerable:
Check the operating system version against the affected versions list. On Apple devices, go to Settings > General > About to view the current version.Check Version:
On macOS: sw_vers. On iOS/iPadOS/tvOS/watchOS/visionOS: Check in Settings > General > About.Verify Fix Applied:
Verify the device is running one of the patched versions: tvOS 26+, watchOS 26+, macOS Sonoma 14.8+, iOS 26+, iPadOS 26+, macOS Sequoia 15.7+, visionOS 26+, iOS 18.7+, or iPadOS 18.7+.📡 Detection & Monitoring
Log Indicators:
- Unexpected UDP connections from unauthorized network segments
- UDP socket binding errors in system logs
Network Indicators:
- UDP traffic to local-only services from external network segments
- Unusual UDP port scanning activity targeting Apple devices
SIEM Query:
source="apple_system_logs" AND (event="UDP_socket_binding" OR event="network_interface_change")🔗 References
- https://support.apple.com/en-us/125108
- https://support.apple.com/en-us/125109
- https://support.apple.com/en-us/125111
- https://support.apple.com/en-us/125112
- https://support.apple.com/en-us/125114
- https://support.apple.com/en-us/125115
- https://support.apple.com/en-us/125116
- http://seclists.org/fulldisclosure/2025/Sep/49
- http://seclists.org/fulldisclosure/2025/Sep/53
- http://seclists.org/fulldisclosure/2025/Sep/54
- http://seclists.org/fulldisclosure/2025/Sep/55
- http://seclists.org/fulldisclosure/2025/Sep/56
- http://seclists.org/fulldisclosure/2025/Sep/57
- http://seclists.org/fulldisclosure/2025/Sep/58
