CVE-2025-29522 in DSL-7740C
Summary
by MITRE • 08/26/2025
D-Link DSL-7740C with firmware DSL7740C.V6.TR069.20211230 was discovered to contain a command injection vulnerability via the ping function.
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Analysis
by VulDB Data Team • 09/03/2025
The vulnerability identified as CVE-2025-29522 affects D-Link DSL-7740C routers running firmware version DSL7740C.V6.TR069.20211230 and represents a critical command injection flaw within the device's ping functionality. This vulnerability resides in the router's web interface where the ping utility is exposed to remote attackers, creating a significant security risk for network infrastructure. The affected device operates as a broadband router with routing capabilities, and the vulnerability specifically targets the command execution mechanism used by the ping function to validate network connectivity.
The technical flaw manifests through improper input validation within the ping implementation, allowing malicious actors to inject arbitrary commands that execute with the privileges of the web server process. This occurs when user-supplied parameters are directly incorporated into system commands without adequate sanitization or escaping mechanisms. The vulnerability falls under CWE-77 and CWE-94 classifications, representing command injection and code injection weaknesses respectively, where attacker-controlled data is interpreted as executable code rather than plain text input. The attack vector requires an authenticated or unauthenticated remote attacker to exploit the vulnerability through the web interface, making it particularly dangerous as it can be leveraged without requiring physical access to the device.
The operational impact of this vulnerability extends beyond simple command execution, as it can enable complete system compromise of the affected router. An attacker could potentially gain unauthorized access to the device's operating system, modify network configurations, redirect traffic, or establish persistence mechanisms within the network infrastructure. This presents a significant risk to enterprise and home network environments where the router serves as a gateway device, potentially allowing attackers to escalate privileges and access internal network resources. The vulnerability affects the device's integrity and availability, as malicious command execution could lead to system instability or complete device compromise, disrupting network services and potentially creating backdoor access points.
Mitigation strategies should focus on immediate firmware updates from D-Link to address the command injection vulnerability, as well as implementing network segmentation and access controls to limit exposure. Network administrators should disable unnecessary services and ensure that the device is not directly exposed to untrusted networks. The vulnerability aligns with ATT&CK technique T1059.001 for command and script injection, and T1071.004 for application layer protocol traffic filtering, indicating that defensive measures should include network monitoring and intrusion detection systems to detect suspicious command execution patterns. Additionally, implementing secure coding practices such as input validation, parameterized queries, and principle of least privilege access controls can help prevent similar vulnerabilities in future deployments. Organizations should also consider network access controls and firewall rules to limit access to the router's management interface to trusted IP addresses only, reducing the attack surface for this and related vulnerabilities.