CVE-2026-30703 in WDR201A
Summary
by MITRE • 03/18/2026
A command injection vulnerability exists in the web management interface of the WiFi Extender WDR201A (HW V2.1, FW LFMZX28040922V1.02). The adm.cgi endpoint improperly sanitizes user-supplied input provided to a command-related parameter in the sysCMD functionality.
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Analysis
by VulDB Data Team • 03/24/2026
This command injection vulnerability resides within the web management interface of the WiFi Extender WDR201A model with hardware version 2.1 and firmware version LFMZX28040922V1.02. The flaw manifests specifically through the adm.cgi endpoint which fails to properly sanitize user-supplied input when processing command-related parameters in the sysCMD functionality. This represents a critical security weakness that directly violates the principle of input validation and sanitization commonly referenced in CWE-77 and CWE-89 categories. The vulnerability allows an attacker to inject arbitrary commands that will be executed with the privileges of the web server process, potentially leading to complete system compromise.
The technical exploitation of this vulnerability occurs when an attacker submits malicious input through parameters that are processed by the sysCMD functionality within the adm.cgi endpoint. This improper sanitization creates an environment where command injection attacks can succeed, enabling attackers to execute arbitrary system commands on the affected device. The vulnerability stems from inadequate input validation mechanisms that fail to properly filter or escape special characters that could alter command execution flow. According to ATT&CK framework category T1059.001, adversaries can leverage such weaknesses to execute commands through the command-line interface, potentially escalating privileges and gaining persistent access to the network infrastructure. The impact extends beyond simple command execution as it provides attackers with the capability to modify system configurations, extract sensitive data, or establish backdoor access points.
The operational consequences of this vulnerability are severe for network administrators and end users who rely on the WDR201A device for wireless connectivity and network management. An attacker who successfully exploits this vulnerability can gain full administrative control over the device, potentially disrupting network services, monitoring traffic, or using the device as a pivot point for attacks on other network segments. The vulnerability affects the device's web management interface, which typically requires authentication, but the command injection flaw allows for remote code execution even when legitimate credentials are not available. This weakness particularly impacts the device's security posture by undermining the trust model that should exist between authorized users and the network infrastructure. The implications are further exacerbated by the fact that many users may not regularly update firmware, leaving devices vulnerable to exploitation for extended periods.
Mitigation strategies for this vulnerability should begin with immediate firmware updates from the vendor to address the input sanitization flaw in the adm.cgi endpoint. Network administrators should implement network segmentation to limit access to management interfaces and employ strong authentication mechanisms including multi-factor authentication where possible. The principle of least privilege should be enforced by restricting access to the web management interface to authorized personnel only and disabling unnecessary services or features. Regular security assessments and network monitoring should be conducted to detect potential exploitation attempts, while implementing web application firewalls to filter suspicious requests targeting the adm.cgi endpoint. According to industry best practices and NIST guidelines, organizations should also maintain comprehensive incident response procedures that include vulnerability assessment, patch management, and network monitoring to effectively respond to such security weaknesses. The vulnerability highlights the critical importance of secure coding practices and input validation in embedded web interfaces, particularly in network infrastructure devices that are often deployed without regular security updates.