CVE-2024-40129
📋 TL;DR
CVE-2024-40129 is a critical buffer overflow vulnerability in Open5GS v2.6.4's PFCP context handling that allows remote attackers to execute arbitrary code or cause denial of service. This affects all systems running vulnerable Open5GS deployments, particularly telecommunications infrastructure using 5G core networks.
💻 Affected Systems
- Open5GS
📦 What is this software?
Open5gs by Open5gs
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete system compromise, data exfiltration, and lateral movement within the network
Likely Case
Denial of service affecting 5G network functionality and potential information disclosure
If Mitigated
Limited impact with proper network segmentation and exploit mitigations in place
🎯 Exploit Status
Buffer overflow in PFCP handling suggests straightforward exploitation for skilled attackers
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Fixed in commit 2fbc445d32aa7749166396a9c055a199f90a1b01
Vendor Advisory: https://github.com/open5gs/open5gs/commit/2fbc445d32aa7749166396a9c055a199f90a1b01
Restart Required: Yes
Instructions:
1. Update Open5GS to latest version or apply commit 2fbc445d32aa7749166396a9c055a199f90a1b01
2. Recompile Open5GS from source
3. Restart all Open5GS services
4. Verify the fix is applied
🔧 Temporary Workarounds
Network Segmentation
linuxRestrict PFCP traffic to trusted sources only using firewall rules
iptables -A INPUT -p udp --dport 8805 -s trusted_ip_range -j ACCEPT
iptables -A INPUT -p udp --dport 8805 -j DROP
🧯 If You Can't Patch
- Implement strict network segmentation to isolate Open5GS from untrusted networks
- Deploy exploit mitigation technologies like ASLR, DEP, and stack canaries
🔍 How to Verify
Check if Vulnerable:
Check Open5GS version and verify if commit 2fbc445d32aa7749166396a9c055a199f90a1b01 is appliedCheck Version:
open5gs --version || check git log for commit 2fbc445d32aa7749166396a9c055a199f90a1b01Verify Fix Applied:
Verify the patched version is running and test PFCP functionality📡 Detection & Monitoring
Log Indicators:
- Abnormal PFCP message sizes
- Segmentation faults in Open5GS logs
- Unexpected process termination
Network Indicators:
- Unusually large PFCP packets
- Malformed PFCP protocol messages
SIEM Query:
source="open5gs.log" AND ("segmentation fault" OR "buffer overflow" OR "SIGSEGV")