A newly discovered vulnerability, CVE-2023-41156, affects Usermin, a popular web-based interface for system user configuration, mailbox handling, password management, and more. This vulnerability is classified as a Stored Cross-Site Scripting (XSS) issue that resides in the filter and forward mail component in Usermin 2.001. Exploiting this vulnerability can allow a remote attacker to inject arbitrary web script or HTML code via the 'save to new folder named' field while creating a new filter in Usermin's mail feature.
Original References
1. CVE-2023-41156 Record
2. SecurityFocus
3. Virtualmin Usermin Changelog
Vulnerability Details
The vulnerability occurs inside Usermin's Mail Filter and Forwarding tab, allowing an attacker to craft a malicious payload and submit it through the 'save to new folder named' field when creating a new e-mail filter. This payload is then stored on the system without proper validation or sanitization, leaving it vulnerable to XSS attacks. Once this malicious payload is triggered, it can lead to unauthorized access to sensitive data, manipulation of web content, and potential execution of additional malicious actions in the context of the current user.
Here is a sample injected script payload that can cause a pop-up alert on the victim's system
<script>alert('XSS Vulnerability CVE-2023-41156')</script>
To exploit the vulnerability, an attacker submits the above payload in the 'save to new folder named' input field when creating a new filter inside the 'Filter and Forward Mail' tab in Usermin. Once successfully stored, this script will execute whenever a victim views the filter list or clicks the corresponding edit button.
Mitigation
The best way to mitigate this vulnerability is to update Usermin to the latest version, which contains security fixes for identified XSS and other security issues. According to the Virtualmin Usermin Changelog, the latest release that addresses this vulnerability is version 2.002. Always ensure that your Usermin installation is up-to-date for protection against known security vulnerabilities.
Limit the access and privileges of Usermin users to the minimum required for their tasks.
3. Regularly audit system security logs and web application logs for indications of compromise or unauthorized access.
4. Implement security awareness training for users to help them avoid phishing attacks and be able to identify and report any suspicious activity.
Conclusion
The Stored Cross-Site Scripting (XSS) vulnerability, CVE-2023-41156, in Usermin's mail filtering feature is a serious security concern that can lead to unauthorized access, data manipulation, and potential further exploitation. Updating to Usermin 2.002 or higher, as well as adhering to security best practices, should effectively mitigate this vulnerability and help maintain overall system security.
Timeline
Published on: 09/14/2023 21:15:10 UTC
Last modified on: 09/19/2023 16:28:17 UTC