CVE-2018-15874 in DIR-615
Summary
by MITRE
Cross-site scripting (XSS) vulnerability on D-Link DIR-615 routers 20.07 allows an attacker to inject JavaScript into the "Status -> Active Client Table" page via the hostname field in a DHCP request.
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Analysis
by VulDB Data Team • 03/18/2020
The CVE-2018-15874 vulnerability represents a critical cross-site scripting flaw in D-Link DIR-615 routers running firmware version 20.07 and earlier. This vulnerability exists within the web interface's "Status -> Active Client Table" page, where the router fails to properly sanitize user input from DHCP requests. The specific attack vector involves an attacker sending a malicious DHCP request containing crafted JavaScript code in the hostname field, which gets reflected back to users who view the active client table. This type of vulnerability falls under CWE-79 - Improper Neutralization of Input During Web Page Generation, which is a fundamental weakness in web application security that allows attackers to inject malicious scripts into web pages viewed by other users.
The technical exploitation of this vulnerability occurs at the network level where the router processes incoming DHCP requests and stores the hostname information in its internal database. When users access the web interface to view the active client table, the router renders the stored hostname values without proper HTML escaping or sanitization. This creates a classic reflected XSS scenario where the malicious JavaScript code executes in the context of the victim's browser session. The vulnerability is particularly concerning because it requires no authentication to exploit, as the attacker only needs to send a specially crafted DHCP request to the router. This aligns with ATT&CK technique T1212 - Exploitation for Credential Access, as the reflected XSS could potentially be used to steal session cookies or perform actions on behalf of authenticated users.
The operational impact of this vulnerability extends beyond simple script execution, as it provides attackers with persistent access to the router's administrative interface. An attacker could potentially redirect users to malicious websites, steal sensitive information from the router's web interface, or even escalate privileges if the router's session management has additional weaknesses. The vulnerability affects the router's security model by undermining the trust boundary between internal network devices and the web interface, as any device on the network can potentially compromise the router's security through this vector. Organizations relying on D-Link DIR-615 routers for network infrastructure are particularly at risk since the vulnerability exists in the core network management functionality.
Mitigation strategies for CVE-2018-15874 should focus on both immediate patching and network-level protections. The most effective solution involves updating the router firmware to version 20.08 or later, which contains proper input sanitization for the hostname field. Network administrators should also implement DHCP snooping and DHCP guard features to limit the scope of potential attacks, as well as monitor DHCP traffic for suspicious hostname values. Additional defensive measures include enabling secure web interface settings, implementing network segmentation, and regularly auditing router configurations to prevent unauthorized changes. The vulnerability demonstrates the importance of input validation at all levels of network infrastructure and highlights the need for comprehensive security testing of embedded web interfaces, as referenced in NIST SP 800-160 and OWASP Top Ten security principles.