CVE-2025-49492
📋 TL;DR
This CVE describes an out-of-bounds write vulnerability in the ASR180x LTE telephony component's dev_api.C file, which could allow attackers to execute arbitrary code or cause denial of service. The vulnerability affects Falcon_Linux, Kestrel, and Lapwing_Linux systems running versions before v1536. Successful exploitation requires access to the affected telephony 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
Remote code execution leading to complete system compromise, data exfiltration, or persistent backdoor installation
Likely Case
Service disruption, denial of service affecting LTE telephony functionality, or limited code execution within the telephony service context
If Mitigated
Service crash requiring restart, with limited impact due to network segmentation and access controls
🎯 Exploit Status
Exploitation requires understanding of the telephony protocol and access to the service interface; no public exploits known at this time
🛠️ 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 firmware from ASR Micro vendor portal. 2. Backup current configuration. 3. Apply firmware update following vendor documentation. 4. Reboot system. 5. Verify version is v1536 or later.
🔧 Temporary Workarounds
Disable telephony service
linuxTemporarily disable the atcmd_server service if LTE telephony functionality is not required
systemctl stop atcmd_server
systemctl disable atcmd_server
Network segmentation
linuxRestrict network access to telephony service ports
iptables -A INPUT -p tcp --dport [telephony_port] -j DROP
iptables -A INPUT -p udp --dport [telephony_port] -j DROP
🧯 If You Can't Patch
- Implement strict network access controls to limit exposure of telephony service interfaces
- Monitor system logs for abnormal telephony service behavior or crash events
🔍 How to Verify
Check if Vulnerable:
Check system version: cat /etc/os-release or vendor-specific version file; if version is earlier than v1536 and telephony service is running, system is vulnerableCheck Version:
cat /proc/version | grep -i 'Falcon\|Kestrel\|Lapwing' || cat /etc/*release* | grep -i 'version'Verify Fix Applied:
Verify version is v1536 or later and check telephony service is functioning normally after patch📡 Detection & Monitoring
Log Indicators:
- Unexpected atcmd_server crashes
- Memory access violation errors in system logs
- Abnormal telephony service restart patterns
Network Indicators:
- Unusual traffic patterns to telephony service ports
- Connection attempts from unexpected sources to telephony interface
SIEM Query:
source="system_logs" AND (process="atcmd_server" AND (event="segmentation fault" OR event="memory violation" OR event="crash"))