CVE-2024-11064
📋 TL;DR
The D-Link DSL6740C modem has an OS command injection vulnerability that allows authenticated attackers with administrator privileges to execute arbitrary system commands via SSH or Telnet. This affects users of this specific modem model who have remote administration enabled.
💻 Affected Systems
- D-Link DSL6740C
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete compromise of the modem allowing attackers to establish persistent access, intercept network traffic, pivot to internal networks, and potentially brick the device.
Likely Case
Attackers with admin credentials can execute commands to modify configurations, steal credentials, or deploy malware on the network.
If Mitigated
Limited impact if remote administration is disabled and strong authentication is enforced.
🎯 Exploit Status
Requires administrator credentials. No public exploit code available at disclosure time.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check D-Link for latest firmware
Vendor Advisory: https://support.dlink.com/
Restart Required: Yes
Instructions:
1. Log into modem web interface. 2. Navigate to firmware update section. 3. Download latest firmware from D-Link support site. 4. Upload and apply firmware update. 5. Reboot modem.
🔧 Temporary Workarounds
Disable Remote Administration
allDisable SSH and Telnet remote access to prevent exploitation
Change Admin Credentials
allUse strong, unique administrator passwords
🧯 If You Can't Patch
- Isolate modem on separate VLAN with restricted access
- Implement network monitoring for suspicious SSH/Telnet activity
🔍 How to Verify
Check if Vulnerable:
Check if SSH/Telnet is enabled and accessible with admin credentials on DSL6740CCheck Version:
Login to web interface and check firmware version in status pageVerify Fix Applied:
Verify firmware version is latest from D-Link and test command injection attempts fail📡 Detection & Monitoring
Log Indicators:
- Unusual SSH/Telnet login attempts
- Suspicious command execution in system logs
- Multiple failed authentication attempts
Network Indicators:
- Unexpected SSH/Telnet connections to modem
- Outbound connections from modem to suspicious IPs
SIEM Query:
source="modem_logs" AND (event="ssh_login" OR event="telnet_login") AND user="admin" AND command="*;*" OR command="*|*" OR command="*`*"