CVE-2023-34101
📋 TL;DR
This vulnerability in Contiki-NG OS allows attackers to trigger out-of-bounds memory reads by sending specially crafted truncated ICMP DAO packets. IoT devices running Contiki-NG version 4.8 or earlier are affected, potentially exposing sensitive memory contents or causing crashes.
💻 Affected Systems
- Contiki-NG Operating System
📦 What is this software?
Contiki Ng by Contiki Ng
⚠️ Risk & Real-World Impact
Worst Case
Information disclosure of up to 16 bytes of adjacent memory, potentially revealing sensitive data or enabling further exploitation leading to remote code execution.
Likely Case
Denial of service through device crashes or instability, with possible information leakage from memory.
If Mitigated
Minimal impact with proper network segmentation and packet filtering preventing malicious ICMP packets from reaching devices.
🎯 Exploit Status
Exploitation requires sending malicious ICMP packets to vulnerable devices, which is straightforward for attackers with network access.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 4.9 (expected), currently available in 'develop' branch
Vendor Advisory: https://github.com/contiki-ng/contiki-ng/security/advisories/GHSA-fp66-ff6x-7w2w
Restart Required: Yes
Instructions:
1. Update to Contiki-NG version 4.9 when released. 2. For immediate fix, apply changes from pull request #2435 to the 'develop' branch. 3. Recompile and redeploy the OS on affected devices.
🔧 Temporary Workarounds
Apply GitHub Pull Request #2435
allManually apply the buffer size validation fix from the Contiki-NG repository
git clone https://github.com/contiki-ng/contiki-ng.git
cd contiki-ng
git checkout develop
git pull origin pull/2435/head
make clean
make TARGET=<your_target>
🧯 If You Can't Patch
- Implement network segmentation to isolate IoT devices from untrusted networks
- Deploy network firewalls or intrusion prevention systems to filter malicious ICMP packets targeting vulnerable devices
🔍 How to Verify
Check if Vulnerable:
Check Contiki-NG version: if running version 4.8 or earlier, device is vulnerable. Review source code for presence of buffer size validation in dao_input_storing function.Check Version:
Check device firmware version or Contiki-NG build configuration files for version informationVerify Fix Applied:
Verify the patch is applied by checking that buffer size validation exists before memory access in dao_input_storing function, or confirm running version 4.9+.📡 Detection & Monitoring
Log Indicators:
- Unexpected device crashes or reboots
- Memory access violation logs
- Abnormal ICMP packet processing errors
Network Indicators:
- Malformed ICMP DAO packets with truncated payloads targeting IoT devices
- Unusual ICMP traffic patterns to IoT network segments
SIEM Query:
source="network_firewall" AND (proto="icmp" AND (payload_size < expected_size OR packet_truncated=true)) AND dest_ip IN (iot_device_ips)