CVE-2007-4318 in Zywall 2
Summary
by MITRE
Cross-site scripting (XSS) vulnerability in Forms/General_1 in the management interface in ZyNOS firmware 3.62(WK.6) on the Zyxel Zywall 2 device allows remote authenticated administrators to inject arbitrary web script or HTML via the sysSystemName parameter.
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Analysis
by VulDB Data Team • 12/02/2024
The vulnerability identified as CVE-2007-4318 represents a critical cross-site scripting flaw within the ZyNOS firmware version 3.62(WK.6) operating on Zyxel Zywall 2 security appliances. This vulnerability exists within the management interface's Forms/General_1 component and specifically targets the sysSystemName parameter, creating a pathway for malicious actors to execute arbitrary web scripts or HTML code. The flaw is particularly concerning because it affects authenticated administrators, meaning that an attacker who has already gained administrative access or can impersonate such a user can leverage this vulnerability to escalate their compromise.
The technical implementation of this XSS vulnerability stems from insufficient input validation and output sanitization within the web interface. When administrators interact with the system configuration through the management interface, the sysSystemName parameter fails to properly sanitize user-supplied input before rendering it back to the browser. This allows malicious payloads to be injected and subsequently executed in the context of other administrators' sessions, potentially enabling session hijacking, credential theft, or unauthorized configuration changes. The vulnerability falls under CWE-79 which specifically addresses Cross-Site Scripting flaws in web applications, where improper validation of input allows malicious scripts to be executed in the victim's browser.
The operational impact of this vulnerability extends beyond simple script injection, as it can be exploited to create persistent malicious web scripts that execute whenever administrators access the management interface. An attacker with authenticated access can modify the system name field to include malicious JavaScript code that would execute in the browser of any administrator who views the system configuration. This could lead to complete compromise of the management interface, allowing attackers to modify firewall rules, access sensitive configuration data, or even redirect administrators to malicious sites that could harvest credentials. The vulnerability also aligns with ATT&CK technique T1078 which covers valid accounts and T1566 which covers credential harvesting through social engineering or compromised administrative interfaces.
Mitigation strategies for this vulnerability require immediate firmware updates from Zyxel to address the XSS implementation flaws in the ZyNOS firmware. Organizations should also implement network segmentation to limit access to management interfaces, enforce strict access controls through multi-factor authentication, and monitor for unusual activity in the management interface logs. Additionally, administrators should be trained to recognize and avoid suspicious links or scripts that may be injected through such vulnerabilities. Regular security assessments of network infrastructure components and maintaining updated vulnerability databases are essential practices to prevent exploitation of similar flaws in other network security devices that may share similar architectural patterns. The vulnerability demonstrates the critical importance of input validation and output encoding in web applications, particularly in administrative interfaces where the potential for privilege escalation exists.