CVE-2021-22680
📋 TL;DR
This CVE describes an integer overflow vulnerability in NXP MQX RTOS memory allocation functions that can lead to arbitrary memory allocation. Attackers could exploit this to cause system crashes or potentially execute remote code. Affected systems include embedded devices using NXP MQX RTOS versions 5.1 and earlier.
💻 Affected Systems
- NXP MQX Real-Time Operating System
📦 What is this software?
Mqx by Nxp
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete system compromise, allowing attackers to take control of affected devices.
Likely Case
System crashes or denial of service due to memory corruption, potentially requiring device reboots.
If Mitigated
Limited impact with proper memory protection mechanisms and network segmentation in place.
🎯 Exploit Status
Exploitation requires triggering specific memory allocation patterns but could be achieved through network input in vulnerable applications.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Version 5.2 or later
Vendor Advisory: https://www.nxp.com/docs/en/security-advisory/CVE-2021-22680.pdf
Restart Required: Yes
Instructions:
1. Obtain MQX RTOS version 5.2 or later from NXP. 2. Recompile applications with patched libraries. 3. Deploy updated firmware to affected devices. 4. Test functionality before production deployment.
🔧 Temporary Workarounds
Memory allocation limits
allImplement bounds checking on memory allocation requests in application code
// Add size validation before calling mem_alloc, _lwmem_alloc, _partition functions
Input validation
allValidate all external inputs that could affect memory allocation sizes
// Implement strict input validation for network/interface data
🧯 If You Can't Patch
- Segment affected devices on isolated networks with strict firewall rules
- Implement monitoring for abnormal memory usage patterns and system crashes
🔍 How to Verify
Check if Vulnerable:
Check MQX RTOS version in firmware or consult device manufacturer documentationCheck Version:
Check firmware version through device management interface or manufacturer toolsVerify Fix Applied:
Verify MQX RTOS version is 5.2 or later and recompile applications with updated libraries📡 Detection & Monitoring
Log Indicators:
- Unexpected system crashes
- Memory allocation failures
- Abnormal process termination
Network Indicators:
- Unusual network traffic to embedded device management ports
- Protocol anomalies in industrial protocols
SIEM Query:
search 'system crash' OR 'memory allocation error' AND device_type='embedded' OR os='MQX'