CVE-2024-11062
📋 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 all users of this specific modem model who have SSH or Telnet enabled. Attackers can gain full control of the device and potentially pivot to internal networks.
💻 Affected Systems
- D-Link DSL6740C
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Full compromise of the modem allowing attackers to intercept all network traffic, install persistent malware, pivot to internal devices, and use the device as a botnet node.
Likely Case
Attackers with stolen or default credentials gain full control of the modem, enabling network traffic monitoring, DNS hijacking, and credential theft from connected devices.
If Mitigated
With SSH/Telnet disabled and strong unique admin credentials, the attack surface is significantly reduced, though physical access or other vulnerabilities could still be exploited.
🎯 Exploit Status
Exploitation requires admin credentials but is straightforward once authenticated. Public technical details available.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check D-Link support for latest firmware
Vendor Advisory: https://support.dlink.com/
Restart Required: Yes
Instructions:
1. Log into modem web interface. 2. Navigate to Management > Firmware Update. 3. Download latest firmware from D-Link support site. 4. Upload and apply update. 5. Reboot modem.
🔧 Temporary Workarounds
Disable SSH and Telnet
allDisable remote administration services to prevent exploitation
Change Default Credentials
allUse strong unique admin password
🧯 If You Can't Patch
- Isolate modem on separate VLAN with strict firewall rules
- Implement network monitoring for suspicious SSH/Telnet activity
🔍 How to Verify
Check if Vulnerable:
Check if SSH/Telnet is enabled and test command injection via authenticated sessionCheck Version:
Log into web interface and check System Status > Firmware VersionVerify Fix Applied:
Verify firmware version is updated and test that command injection no longer works📡 Detection & Monitoring
Log Indicators:
- Unusual SSH/Telnet login attempts
- Suspicious command execution in system logs
- Multiple failed authentication attempts
Network Indicators:
- Unexpected outbound connections from modem
- SSH/Telnet traffic to unusual destinations
- DNS queries to malicious domains
SIEM Query:
source="modem_logs" AND (event="ssh_login" OR event="telnet_login") AND user="admin" AND result="success"