CVE-2026-3716 in WL-WN579X3-C
Summary
by MITRE • 03/08/2026
A vulnerability was determined in Wavlink WL-WN579X3-C 231124. This vulnerability affects the function sub_401AD4 of the file /cgi-bin/adm.cgi. Executing a manipulation of the argument Hostname can lead to cross site scripting. It is possible to launch the attack remotely. The exploit has been publicly disclosed and may be utilized. Upgrading to version 20260226 is able to resolve this issue. The affected component should be upgraded. The vendor was contacted early, responded in a very professional manner and quickly released a fixed version of the affected product.
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Analysis
by VulDB Data Team • 03/12/2026
The vulnerability identified as CVE-2026-3716 resides within the Wavlink WL-WN579X3-C 231124 wireless router firmware, specifically targeting the sub_401AD4 function located in the /cgi-bin/adm.cgi file. This represents a critical cross-site scripting vulnerability that arises from inadequate input validation when processing the Hostname parameter. The flaw exists in the web interface component of the device, which is accessible through standard HTTP requests to the administrative console. The vulnerability's presence in the cgi-bin directory indicates it operates within the web server's executable environment where user-supplied data is processed and potentially rendered back to users without proper sanitization mechanisms.
The technical exploitation of this vulnerability occurs when an attacker manipulates the Hostname argument parameter, which is then processed by the sub_401AD4 function. This function fails to properly sanitize or escape user input before incorporating it into dynamic web content, creating a classic XSS attack vector. The remote exploitability aspect means that attackers can trigger this vulnerability through network-based attacks without requiring physical access to the device or local network credentials. The attack surface extends to any user who accesses the router's web administration interface, particularly administrators who might be logged in with elevated privileges. This vulnerability falls under CWE-79 which specifically addresses Cross-Site Scripting flaws in web applications, making it a well-documented and dangerous class of vulnerability.
The operational impact of this vulnerability is significant as it allows attackers to execute malicious scripts within the context of the victim's browser session. An attacker could potentially steal administrative credentials, modify router configuration settings, redirect users to malicious websites, or perform other malicious activities that compromise the network security. The router's administrative interface becomes a potential entry point for broader network attacks, as compromised administrative sessions could provide access to internal network resources. The vulnerability's public disclosure status increases the risk level considerably, as it may already be in use by threat actors who are actively exploiting this weakness. The affected device operates in a critical network position serving as a gateway between internal and external networks, making its compromise particularly dangerous for organizations relying on the device for network security.
The vendor's response to this vulnerability demonstrates responsible disclosure practices, with early contact and rapid release of a patched firmware version 20260226. This timely remediation aligns with industry best practices for vulnerability management and shows the vendor's commitment to maintaining product security. The recommended mitigation approach involves immediate firmware upgrading to version 20260226, which contains the necessary code modifications to properly sanitize the Hostname parameter input. Network administrators should also implement additional monitoring of the device's administrative interface for suspicious access patterns and consider implementing network segmentation to limit potential lateral movement if exploitation occurs. The vulnerability's classification under the ATT&CK framework would likely fall under T1071.004 for application layer protocol usage and potentially T1566 for social engineering techniques that might be employed in conjunction with this vulnerability. Organizations should also consider implementing web application firewalls or content security policies to provide additional protection layers against similar XSS vulnerabilities in their network infrastructure.