CVE-2025-11618
📋 TL;DR
A missing validation check in FreeRTOS-Plus-TCP's UDP/IPv6 packet processing can cause an invalid pointer dereference when receiving a UDP/IPv6 packet with an incorrect IP version field in the header. This vulnerability may lead to denial-of-service or system instability, affecting only applications using IPv6 in FreeRTOS-Plus-TCP.
💻 Affected Systems
- FreeRTOS-Plus-TCP
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
System crash or denial-of-service due to invalid pointer dereference, potentially disrupting device functionality in embedded systems.
Likely Case
Denial-of-service or instability in affected devices when processing malformed UDP/IPv6 packets, leading to temporary unavailability.
If Mitigated
Minimal impact if patched or if IPv6 is disabled; systems may experience no disruption with proper network controls.
🎯 Exploit Status
Exploitation requires sending a malformed UDP/IPv6 packet to an affected device, but no public proof-of-concept is available, and it may be challenging to achieve reliable results.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: V4.3.4
Vendor Advisory: https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/security/advisories/GHSA-6fh9-mqxj-hmwj
Restart Required: No
Instructions:
1. Upgrade FreeRTOS-Plus-TCP to version V4.3.4 or later. 2. Download from the official GitHub releases. 3. Replace the existing FreeRTOS-Plus-TCP source files with the patched version. 4. Recompile and redeploy the application. 5. Verify the fix by testing with IPv6 traffic.
🔧 Temporary Workarounds
Disable IPv6
allIf IPv6 is not required, disable it in the FreeRTOS-Plus-TCP configuration to prevent processing of IPv6 packets and mitigate the vulnerability.
Set ipconfigUSE_IPv6 to 0 in FreeRTOSIPConfig.h or equivalent configuration file.
🧯 If You Can't Patch
- Implement network filtering to block or inspect UDP/IPv6 packets from untrusted sources, reducing exposure to malformed packets.
- Monitor system logs for crashes or anomalies related to UDP/IPv6 processing and isolate affected devices if issues occur.
🔍 How to Verify
Check if Vulnerable:
Check the FreeRTOS-Plus-TCP version in use; if it is prior to V4.3.4 and IPv6 is enabled, the system is vulnerable.Check Version:
Inspect the source code or build configuration for the FreeRTOS-Plus-TCP version, typically defined in version headers or build scripts.Verify Fix Applied:
After patching, confirm the version is V4.3.4 or later and test by sending UDP/IPv6 packets to ensure no crashes or pointer dereference errors occur.📡 Detection & Monitoring
Log Indicators:
- System crashes, reboots, or error logs related to UDP/IPv6 packet processing or invalid pointer dereferences in FreeRTOS-Plus-TCP.
Network Indicators:
- Unusual UDP/IPv6 traffic patterns or spikes in malformed packets directed at devices running FreeRTOS-Plus-TCP.
SIEM Query:
Search for logs containing 'FreeRTOS-Plus-TCP', 'IPv6', 'UDP', 'crash', or 'dereference' from embedded devices or IoT systems.