CVE-2024-11062 Overview
CVE-2024-11062 is an OS Command Injection vulnerability [CWE-78] in the D-Link DSL6740C modem. The flaw exists in a specific functionality exposed through the device's SSH and Telnet management interfaces. Remote attackers holding administrator credentials can inject and execute arbitrary system commands on the underlying operating system. Successful exploitation grants full command execution on the modem, compromising confidentiality, integrity, and availability of the device.
Critical Impact
An authenticated administrator can execute arbitrary OS commands on the D-Link DSL6740C modem over the network via SSH or Telnet, enabling full device takeover and potential pivoting into the connected network.
Affected Products
- D-Link DSL6740C modem (hardware)
- D-Link DSL6740C firmware (all versions listed in the TW-CERT advisory)
- Deployments exposing SSH or Telnet management interfaces
Discovery Timeline
- 2024-11-11 - CVE-2024-11062 published to NVD
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2024-11062
Vulnerability Analysis
The vulnerability is classified as an OS Command Injection issue under [CWE-78]. The DSL6740C modem exposes administrative functionality through SSH and Telnet services. One or more of the command handlers accessible to authenticated administrators concatenate user-supplied input into shell commands without sufficient sanitization. Attackers with valid administrator credentials can supply crafted input that breaks out of the intended command context and executes arbitrary operating system commands.
The attack is executed over the network and does not require user interaction. Because the modem runs administrative services with high privileges, injected commands execute in a privileged context on the device.
Root Cause
The root cause is improper neutralization of special elements used in OS commands within a specific administrative function reachable via SSH and Telnet. Input passed from the authenticated management session is used to construct a shell command without proper input validation, escaping, or the use of safe command execution APIs.
Attack Vector
Exploitation requires network reachability to the modem's SSH or Telnet service and valid administrator credentials. An attacker authenticates to the management interface, invokes the affected functionality, and supplies shell metacharacters within a parameter that is passed to the OS command handler. The injected payload executes with the privileges of the management service, typically root on embedded Linux modems.
No verified public exploit or proof-of-concept has been published. Refer to the TW-CERT Security Advisory #139 and TW-CERT Security Advisory #132 for vendor-published technical details.
Detection Methods for CVE-2024-11062
Indicators of Compromise
- Unexpected SSH or Telnet administrative logins to the DSL6740C from external or unusual source addresses.
- Anomalous outbound connections from the modem to attacker-controlled infrastructure following an administrative session.
- Configuration changes, new user accounts, or firmware modifications made outside approved change windows.
- Presence of shell metacharacters such as ;, |, &&, or backticks in device management command logs.
Detection Strategies
- Monitor SSH and Telnet authentication logs on the modem for successful logins from unauthorized source IPs.
- Alert on administrative command input containing shell metacharacters or command-chaining sequences.
- Correlate management-plane authentication events with subsequent outbound network activity from the modem.
Monitoring Recommendations
- Forward modem syslog and authentication events to a centralized log platform for retention and analysis.
- Baseline normal administrative activity so deviations in command frequency, source, or content trigger alerts.
- Track firmware version, configuration hashes, and running services to identify unauthorized changes.
How to Mitigate CVE-2024-11062
Immediate Actions Required
- Restrict SSH and Telnet access to a dedicated management network or trusted administrative hosts only.
- Disable Telnet entirely where feasible, since it transmits credentials in cleartext.
- Rotate administrator credentials on all DSL6740C devices and enforce strong, unique passwords.
- Apply the vendor firmware update referenced in the TW-CERT advisories as soon as it is available for your region.
Patch Information
D-Link has coordinated disclosure through TW-CERT. Consult the TW-CERT Security Advisory #139 and TW-CERT Security Advisory #132 for the fixed firmware version and download instructions applicable to the DSL6740C. No CISA KEV listing or known exploitation in the wild has been reported for this CVE at the time of publication.
Workarounds
- Block inbound access to SSH (TCP/22) and Telnet (TCP/23) from the WAN interface at the modem or upstream firewall.
- Limit administrative logins to a jump host or VPN-restricted management VLAN.
- Remove or disable unused administrator accounts and audit remaining accounts regularly.
- Monitor and rate-limit failed authentication attempts on management services to reduce credential-abuse risk.
# Configuration example: restrict management access at an upstream firewall
# (adjust interface and management CIDR to your environment)
iptables -A FORWARD -i wan0 -p tcp --dport 22 -j DROP
iptables -A FORWARD -i wan0 -p tcp --dport 23 -j DROP
iptables -A FORWARD -s 10.10.0.0/24 -p tcp --dport 22 -d <modem_ip> -j ACCEPT
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
