CVE-2014-3886 in Webmin
Summary
by MITRE
Cross-site scripting (XSS) vulnerability in Webmin before 1.690, when referrer checking is disabled, allows remote attackers to inject arbitrary web script or HTML via unspecified vectors. NOTE: this might overlap CVE-2014-3924.
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Analysis
by VulDB Data Team • 08/04/2021
The CVE-2014-3886 vulnerability represents a critical cross-site scripting flaw in Webmin versions prior to 1.690 that significantly compromises web application security. This vulnerability specifically manifests when the referrer checking mechanism is disabled within the Webmin administration interface, creating an exploitable condition that enables remote attackers to inject malicious scripts into web pages viewed by unsuspecting users. The vulnerability's exploitation occurs through unspecified vectors that leverage the absence of proper input validation and output encoding mechanisms within the Webmin framework.
The technical implementation of this XSS vulnerability stems from insufficient sanitization of user-supplied input data within the Webmin administrative console. When referrer checking is disabled, the system fails to properly validate and escape data before rendering it in web responses, allowing attackers to inject malicious JavaScript code or HTML content that executes in the context of other users' browsers. This weakness operates at the application layer and directly violates the principle of input validation and output encoding that forms the foundation of secure web application development practices. The vulnerability's classification aligns with CWE-79, which specifically addresses cross-site scripting flaws in web applications, and represents a classic example of how improper data handling can lead to severe security consequences.
The operational impact of CVE-2014-3886 extends beyond simple script injection, as it provides attackers with potential access to sensitive administrative functions and user data. Successful exploitation could enable attackers to steal session cookies, perform unauthorized administrative actions, redirect users to malicious sites, or extract confidential information from the Webmin interface. The vulnerability's significance increases when considering that Webmin serves as a critical system administration tool for many organizations, making it an attractive target for attackers seeking persistent access to server environments. This vulnerability directly maps to ATT&CK technique T1059.007, which covers scripting through web shell execution, and represents a fundamental failure in web application security controls that could lead to complete system compromise.
Mitigation strategies for CVE-2014-3886 primarily focus on immediate remediation through software updates and configuration hardening. Organizations must upgrade to Webmin version 1.690 or later, which includes proper input validation and output encoding mechanisms to prevent XSS injection. Additionally, enabling referrer checking within Webmin configuration settings provides an additional layer of protection against this vulnerability. Security practitioners should implement comprehensive input validation across all user-facing interfaces and ensure that proper output encoding is applied to all dynamic content. Network segmentation and access controls should be implemented to limit exposure of Webmin interfaces to trusted networks only, while regular security assessments should verify that no other similar vulnerabilities exist within the application stack. The vulnerability serves as a reminder of the critical importance of maintaining up-to-date software versions and implementing defense-in-depth strategies to protect against common web application attacks.