CVE-2026-4164 is a command injection vulnerability identified in the Wavlink WL-WN578W2 router firmware version 221110. The vulnerability resides in the POST request handler of the /cgi-bin/wireless.cgi script, affecting functions such as Delete_Mac_list, SetName, and GuestWifi. These functions improperly sanitize user input, allowing an attacker to inject arbitrary OS commands remotely without authentication or user interaction. The vulnerability enables full compromise of the device, potentially allowing attackers to execute commands with the privileges of the web server process, which often runs with elevated rights on embedded devices. The CVSS 4.0 score of 9.3 reflects the ease of exploitation (network attack vector, no privileges or user interaction required) and the high impact on confidentiality, integrity, and availability. Although no active exploitation has been reported, a public exploit is available, increasing the likelihood of attacks. The affected device is commonly used in small office/home office (SOHO) environments, making it a target for attackers seeking to establish footholds or pivot into internal networks. The lack of a patch or official update at the time of disclosure necessitates immediate mitigation efforts to reduce exposure.

The impact of this vulnerability is severe for organizations using the Wavlink WL-WN578W2 router, as successful exploitation allows remote attackers to execute arbitrary commands on the device. This can lead to full device compromise, enabling attackers to intercept, modify, or disrupt network traffic, create persistent backdoors, or launch further attacks against internal network resources. Confidentiality is at risk because attackers can access sensitive network configuration and data. Integrity is compromised as attackers can alter device settings or inject malicious code. Availability can be disrupted by executing commands that crash or disable the device. Given the device’s role as a network gateway, exploitation could facilitate lateral movement within corporate or home networks, potentially affecting connected systems and data. The public availability of an exploit increases the risk of widespread attacks, especially in environments where firmware updates are not promptly applied.

To mitigate CVE-2026-4164, organizations should immediately check if they are using the Wavlink WL-WN578W2 router with firmware version 221110 and upgrade to a patched firmware version as soon as it becomes available from the vendor. In the absence of an official patch, network administrators should disable remote management interfaces and restrict access to the router’s web interface to trusted internal IP addresses only. Implement network segmentation to isolate vulnerable devices from critical infrastructure and sensitive data. Monitor network traffic and device logs for unusual POST requests to /cgi-bin/wireless.cgi or other suspicious activity indicative of exploitation attempts. Employ intrusion detection/prevention systems (IDS/IPS) with signatures targeting this vulnerability or related command injection patterns. Regularly audit device configurations and update all network devices to the latest firmware versions to reduce the attack surface. Educate users about the risks of using outdated firmware and encourage timely updates.