CVE-2018-15602 in VMG3312 B10B
Summary
by MITRE
Zyxel VMG3312 B10B devices are affected by a persistent XSS vulnerability via the pages/connectionStatus/connectionStatus-hostEntry.cmd hostname parameter.
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Analysis
by VulDB Data Team • 03/18/2020
The CVE-2018-15602 vulnerability affects Zyxel VMG3312 B10B broadband routers, representing a critical persistent cross-site scripting flaw that undermines the security of network infrastructure devices. This vulnerability resides within the web interface of the router's administrative console, specifically targeting the connectionStatus-hostEntry.cmd page where the hostname parameter is improperly sanitized. The flaw allows attackers to inject malicious scripts that persistently execute in the context of the victim's browser session, potentially compromising the entire network administration interface.
The technical implementation of this vulnerability stems from inadequate input validation and output encoding within the router's web application framework. When users interact with the connection status page and manipulate the hostname parameter through the URL, the device fails to properly sanitize user-supplied data before incorporating it into dynamically generated HTML content. This weakness creates an ideal environment for persistent XSS attacks where malicious payloads can be stored and executed whenever the affected page is accessed, making it particularly dangerous for network administrators who regularly monitor connection status information.
From an operational impact perspective, this vulnerability poses significant risks to enterprise and home network security. An attacker who successfully exploits this flaw can gain unauthorized access to the router's administrative interface, potentially leading to complete network compromise. The persistent nature of the vulnerability means that malicious scripts remain active even after the initial exploit, allowing attackers to maintain long-term access to the device. Network administrators may unknowingly execute malicious code while performing routine monitoring tasks, providing attackers with continuous access to sensitive network information and configuration data.
The vulnerability aligns with CWE-79 Cross-site Scripting and maps to ATT&CK technique T1059.007 Command and Scripting Interpreter for Web Shell execution. Organizations should immediately implement network segmentation to isolate affected devices from critical network segments and deploy web application firewalls to detect and block malicious script injection attempts. Regular firmware updates from Zyxel should be prioritized, and network administrators should conduct thorough security assessments of all router configurations. Additional mitigations include implementing strict input validation at the network perimeter, disabling unnecessary web management interfaces, and establishing monitoring protocols to detect anomalous access patterns to router administrative interfaces. The persistent nature of this vulnerability underscores the importance of comprehensive security hygiene and regular vulnerability assessments to prevent exploitation of similar flaws in network infrastructure devices.