CVE-2025-49491
📋 TL;DR
This CVE describes an improper resource shutdown vulnerability in ASR's traffic_stat modules on Linux systems, allowing resource leak exposure. It affects Falcon_Linux, Kestrel, and Lapwing_Linux products before version 1536. Attackers could potentially exhaust system resources, leading to denial of service.
💻 Affected Systems
- Falcon_Linux
- Kestrel
- Lapwing_Linux
📦 What is this software?
Falcon Linux by Asrmicro
Kestrel by Asrmicro
Lapwing Linux by Asrmicro
⚠️ Risk & Real-World Impact
Worst Case
Complete system resource exhaustion causing denial of service, potentially affecting multiple services on the host
Likely Case
Gradual performance degradation and instability of the affected traffic_stat service
If Mitigated
Minor performance impact limited to the specific service module
🎯 Exploit Status
Exploitation requires ability to trigger the resource leak condition repeatedly
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: v1536
Vendor Advisory: https://www.asrmicro.com/en/goods/psirt?cid=40
Restart Required: Yes
Instructions:
1. Download v1536 or later from ASR vendor portal. 2. Backup current configuration. 3. Install the update following vendor documentation. 4. Restart affected services.
🔧 Temporary Workarounds
Disable traffic_stat module
linuxTemporarily disable the vulnerable traffic_stat module if not essential
systemctl stop traffic_service
systemctl disable traffic_service
Resource monitoring and limits
linuxImplement resource limits and monitoring to detect abnormal consumption
# Set ulimits for the service process
# Monitor with: watch -n 1 'ps aux | grep traffic_service'
🧯 If You Can't Patch
- Implement strict network segmentation to limit access to affected systems
- Deploy resource monitoring and alerting for abnormal memory/file descriptor usage
🔍 How to Verify
Check if Vulnerable:
Check current version: cat /etc/asr-version or asr-version command. If version is below 1536 and traffic_service is running, system is vulnerable.Check Version:
asr-version || cat /etc/asr-versionVerify Fix Applied:
Verify version is 1536 or higher and monitor traffic_service for resource leaks using: watch -n 5 'lsof -p $(pgrep traffic_service) | wc -l'📡 Detection & Monitoring
Log Indicators:
- Repeated traffic_service crashes
- Resource exhaustion warnings in system logs
- High file descriptor usage by traffic_service
Network Indicators:
- Unusual traffic patterns to/from traffic_stat ports
- Service unavailability alerts
SIEM Query:
process_name="traffic_service" AND (event_type="crash" OR resource_usage>threshold)