CVE-2017-2106 in Webmin
Summary
by MITRE
Multiple cross-site scripting vulnerabilities in Webmin versions prior to 1.830 allows remote attackers to inject arbitrary web script or HTML via unspecified vectors.
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Analysis
by VulDB Data Team • 12/02/2022
The vulnerability identified as CVE-2017-2106 represents a critical cross-site scripting weakness affecting Webmin versions prior to 1.830. This flaw falls under the broader category of CWE-79 Improper Neutralization of Input During Web Page Generation, which specifically addresses the failure to properly sanitize user input before incorporating it into web content. The vulnerability exists within the web-based administration interface of Webmin, a popular open-source web-based system administration tool that allows administrators to manage various server components through a graphical user interface. The affected versions of Webmin fail to adequately validate or escape user-supplied data when processing requests, creating opportunities for malicious actors to inject malicious scripts into web pages viewed by other users.
The technical exploitation of this vulnerability occurs through unspecified vectors that likely involve user input fields or parameters within the Webmin interface. Attackers can craft malicious payloads that, when processed by the vulnerable Webmin application, get executed in the context of other users' browsers. This type of vulnerability enables attackers to perform various malicious activities including session hijacking, credential theft, defacement of web interfaces, and potentially gaining unauthorized access to server resources. The impact extends beyond simple script execution as it can lead to complete compromise of the administrative interface, allowing attackers to manipulate system configurations, access sensitive data, or even escalate privileges within the affected environment. The vulnerability's classification as a remote attack vector means that no local access or authentication is required to exploit it, making it particularly dangerous in environments where Webmin is accessible from untrusted networks.
The operational implications of CVE-2017-2106 are severe for organizations relying on Webmin for system administration. Given that Webmin is commonly used to manage critical server components including user accounts, file systems, network configurations, and service management, successful exploitation could provide attackers with comprehensive access to the underlying systems. The vulnerability's presence in versions prior to 1.830 indicates that it was likely present for an extended period, potentially allowing attackers to establish persistent access and conduct reconnaissance activities. Organizations using vulnerable versions face risks of data breaches, unauthorized system modifications, and potential lateral movement within their network infrastructure. The vulnerability also aligns with ATT&CK technique T1059.007 Command and Scripting Interpreter: JavaScript, as attackers can leverage the XSS flaw to execute malicious JavaScript code in the victim's browser context.
Mitigation strategies for this vulnerability primarily involve immediate upgrading to Webmin version 1.830 or later, which contains the necessary patches to address the cross-site scripting issues. System administrators should also implement additional defensive measures including input validation and output encoding mechanisms, web application firewalls, and regular security assessments of web-based management interfaces. The vulnerability demonstrates the importance of maintaining up-to-date software versions and implementing proper input sanitization practices. Organizations should also consider implementing additional security controls such as network segmentation, access controls, and monitoring for suspicious activities in their Webmin interfaces. Regular security audits and vulnerability assessments should be conducted to identify similar weaknesses in other web applications and systems. The remediation process should include comprehensive testing of the patched version to ensure that all XSS vectors have been properly addressed and that legitimate functionality remains intact.