CVE-2023-45573
📋 TL;DR
A critical buffer overflow vulnerability in multiple D-Link router models allows remote attackers to execute arbitrary code by exploiting the 'n' parameter in the mrclfile_del.asp function. This affects D-Link DI-7003GV2, DI-7100G+V2, DI-7100GV2, DI-7200G+V2, DI-7200GV2, DI-7300G+V2, and DI-7400G+V2 devices running vulnerable firmware versions. Attackers can gain complete control of affected devices without authentication.
💻 Affected Systems
- D-Link DI-7003GV2.D1
- D-Link DI-7100G+V2.D1
- D-Link DI-7100GV2.D1
- D-Link DI-7200G+V2.D1
- D-Link DI-7200GV2.E1
- D-Link DI-7300G+V2.D1
- D-Link DI-7400G+V2.D1
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete device compromise leading to persistent backdoor installation, network traffic interception, lateral movement to internal networks, and use as botnet nodes for DDoS attacks or cryptocurrency mining.
Likely Case
Remote code execution allowing attackers to modify device configuration, steal credentials, intercept network traffic, and use the device as a pivot point for further attacks.
If Mitigated
Limited impact if devices are behind firewalls with strict inbound filtering, though internal network exposure remains if exploited from within the network.
🎯 Exploit Status
Public proof-of-concept exists in GitHub repositories. The vulnerability requires no authentication and has simple exploitation vectors, making it attractive for mass exploitation.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: Not available
Restart Required: Yes
Instructions:
1. Check D-Link security advisories for firmware updates. 2. Download latest firmware from D-Link support portal. 3. Log into router web interface. 4. Navigate to System Tools > Firmware Upgrade. 5. Upload new firmware file. 6. Wait for automatic reboot.
🔧 Temporary Workarounds
Disable Remote Management
allPrevent external access to the vulnerable web interface
Log into router web interface > System Tools > Remote Management > Disable
Network Segmentation
allIsolate affected devices from critical network segments
Configure firewall rules to restrict access to router management interface
🧯 If You Can't Patch
- Replace affected devices with patched or different vendor equipment
- Implement strict network access controls to limit exposure to management interfaces
🔍 How to Verify
Check if Vulnerable:
Check firmware version in router web interface under System Tools > Firmware InformationCheck Version:
curl -k https://[router-ip]/getcfg.php | grep -i firmwareVerify Fix Applied:
Verify firmware version is newer than affected versions listed in advisory📡 Detection & Monitoring
Log Indicators:
- Unusual POST requests to mrclfile_del.asp with long 'n' parameters
- Multiple failed exploit attempts
- Unexpected configuration changes
Network Indicators:
- Unusual outbound connections from router
- Traffic to known exploit servers
- Port scanning originating from router
SIEM Query:
source="router_logs" AND (uri="*mrclfile_del.asp*" AND param="*n=*" AND length(param)>100)