CVE-2025-63927
📋 TL;DR
A heap-use-after-free vulnerability in airpig2011 IEC104 software allows attackers to cause program crashes or memory corruption by exploiting improper memory handling during multi-threaded execution. This affects systems running vulnerable versions of the IEC104 implementation, potentially leading to denial-of-service conditions. The vulnerability is present in the Iec10x_Scheduled function when accessed by multiple client threads simultaneously.
💻 Affected Systems
- airpig2011 IEC104
📦 What is this software?
Iec104 by Airpig2011
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution through memory corruption leading to complete system compromise, though this requires specific memory layout conditions and exploit development.
Likely Case
Denial-of-service through application crashes, disrupting IEC104 protocol communication and industrial control system operations.
If Mitigated
Application instability with occasional crashes but no persistent impact if proper segmentation and monitoring are in place.
🎯 Exploit Status
Exploitation requires understanding of IEC104 protocol and multi-threading timing. No public exploit code has been identified as of the CVE publication.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Not available
Vendor Advisory: https://github.com/airpig2011/IEC104/issues/20
Restart Required: Yes
Instructions:
1. Monitor the GitHub repository for patches. 2. Consider migrating to a maintained IEC104 implementation. 3. If source code is available, implement proper memory management and thread synchronization in Iec10x_Scheduled function.
🔧 Temporary Workarounds
Disable multi-threaded client execution
allConfigure the IEC104 implementation to use single-threaded client execution mode to prevent the race condition
# Configuration depends on specific implementation. Check software documentation for thread configuration options.
Network segmentation
linuxIsolate IEC104 systems from untrusted networks to reduce attack surface
# Use firewall rules to restrict access to IEC104 ports (typically 2404/TCP)
iptables -A INPUT -p tcp --dport 2404 -s trusted_network -j ACCEPT
iptables -A INPUT -p tcp --dport 2404 -j DROP
🧯 If You Can't Patch
- Implement strict network access controls to limit connections to trusted sources only
- Deploy application monitoring and restart mechanisms to detect and recover from crashes
🔍 How to Verify
Check if Vulnerable:
Check the software version or commit hash. If using airpig2011 IEC104 at or before commit be6d841 (2019-07-08), the system is vulnerable.Check Version:
# For git repositories: git log --oneline -1
# Check for commit be6d841 or earlier in the historyVerify Fix Applied:
Verify that the software has been updated to a version after commit be6d841 or that multi-threaded execution has been disabled.📡 Detection & Monitoring
Log Indicators:
- Application crashes with segmentation faults or memory access errors
- Multiple threads accessing Iec10x_Scheduled simultaneously in debug logs
- Unexpected process termination of IEC104 service
Network Indicators:
- Multiple rapid connections to IEC104 port (2404/TCP) from single source
- Abnormal IEC104 protocol message sequences
SIEM Query:
source="iec104.log" AND ("segmentation fault" OR "memory access" OR "heap corruption" OR "use-after-free")