CVE-2021-38425
📋 TL;DR
CVE-2021-38425 is a vulnerability in eProsima Fast DDS that allows attackers to send specially crafted packets to flood target devices with unwanted traffic. This can cause denial-of-service conditions and potentially expose sensitive information. Organizations using Fast DDS versions prior to 2.4.0 in industrial control systems or IoT deployments are affected.
💻 Affected Systems
- eProsima Fast DDS
📦 What is this software?
Fast Dds by Eprosima
⚠️ Risk & Real-World Impact
Worst Case
Complete system unavailability due to resource exhaustion, potential information disclosure through memory leaks, and disruption of critical industrial processes.
Likely Case
Service degradation or temporary denial-of-service affecting data distribution functionality in affected systems.
If Mitigated
Minimal impact with proper network segmentation, rate limiting, and updated software.
🎯 Exploit Status
Exploitation requires sending specially crafted network packets to vulnerable Fast DDS instances.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 2.4.0
Vendor Advisory: https://github.com/eProsima/Fast-DDS
Restart Required: Yes
Instructions:
1. Update Fast DDS to version 2.4.0 or later. 2. Recompile applications using Fast DDS with the updated library. 3. Restart all services using Fast DDS.
🔧 Temporary Workarounds
Network Segmentation
allIsolate Fast DDS instances from untrusted networks using firewalls or network segmentation.
Rate Limiting
allImplement network rate limiting to restrict packet flooding attempts.
🧯 If You Can't Patch
- Implement strict network access controls to limit which systems can communicate with Fast DDS instances.
- Deploy intrusion detection systems to monitor for packet flooding patterns and anomalous traffic.
🔍 How to Verify
Check if Vulnerable:
Check Fast DDS version using the application's version command or by examining linked libraries.Check Version:
Check application documentation for version command or use: ldd <application> | grep fastrtpsVerify Fix Applied:
Verify Fast DDS version is 2.4.0 or later and monitor for packet flooding attempts.📡 Detection & Monitoring
Log Indicators:
- Unusual increase in packet processing errors
- Resource exhaustion warnings
- High CPU/memory usage by Fast DDS processes
Network Indicators:
- Sudden spikes in network traffic to Fast DDS ports
- Unusual packet patterns from single sources
- TCP/UDP flood patterns
SIEM Query:
source_port:7400 OR dest_port:7400 AND (bytes > 1000000 OR packets > 1000) WITHIN 1 MINUTE