CVE-2026-1705 in DSL-6641K
Summary
by MITRE • 01/31/2026
A vulnerability was detected in D-Link DSL-6641K N8.TR069.20131126. Affected by this issue is the function ad_virtual_server_vdsl of the component Web Interface. Performing a manipulation of the argument Name results in cross site scripting. It is possible to initiate the attack remotely. The exploit is now public and may be used.
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Analysis
by VulDB Data Team • 01/31/2026
The vulnerability identified as CVE-2026-1705 affects the D-Link DSL-6641K router firmware version N8.TR069.20131126, specifically within the Web Interface component. This issue resides in the ad_virtual_server_vdsl function where insufficient input validation occurs for the Name argument parameter. The flaw represents a classic cross-site scripting vulnerability that allows remote attackers to inject malicious script code into web responses. The vulnerability is particularly concerning as it operates through the web interface, making it accessible to anyone who can reach the device's management portal without requiring physical access or specialized privileges. The affected component processes user-supplied data without proper sanitization, creating an attack surface that can be exploited through web-based interactions.
The technical implementation of this vulnerability stems from inadequate parameter validation within the web interface's virtual server configuration function. When the Name argument is manipulated during virtual server creation or modification processes, the system fails to properly encode or filter special characters that could be interpreted as executable script code. This processing gap enables attackers to inject malicious JavaScript payloads that execute within the context of other users' browsers who access the affected web interface. The vulnerability is classified under CWE-79 as a cross-site scripting flaw, which occurs when user input is directly incorporated into web pages without proper sanitization or encoding mechanisms. The attack vector is remote and requires no authentication, as the web interface is accessible to unauthenticated users who can interact with the device's management functions.
The operational impact of this vulnerability extends beyond simple script injection, as it can be leveraged for more sophisticated attacks within the network environment. An attacker could potentially redirect users to malicious sites, steal session cookies, or even execute arbitrary commands on the affected device if additional vulnerabilities exist. The public availability of exploits for this vulnerability increases the risk profile significantly, as it removes the need for advanced technical skills to mount attacks. The web interface serves as a potential entry point for broader network compromise, especially in environments where users might access the device management portal from various locations. This vulnerability particularly affects enterprise and residential networks where D-Link DSL-6641K devices are deployed, creating potential for widespread impact through credential theft or further exploitation attempts.
Mitigation strategies for this vulnerability should prioritize immediate firmware updates from D-Link to address the identified cross-site scripting flaw. Network administrators should implement strict access controls limiting web interface access to trusted IP addresses and consider disabling remote management capabilities where possible. The implementation of web application firewalls and content security policies can help detect and prevent malicious script injection attempts. Additionally, regular security assessments should verify that no other components within the device firmware contain similar input validation flaws. Organizations should also consider network segmentation to limit the potential impact of successful exploitation attempts and implement monitoring solutions to detect unusual traffic patterns that might indicate exploitation attempts. The vulnerability aligns with ATT&CK technique T1566 related to phishing and credential theft through web-based attacks, emphasizing the need for comprehensive defensive measures.