CVE-2022-36880 in Webmin
Summary
by MITRE • 07/27/2022
The Read Mail module in Webmin 1.995 and Usermin through 1.850 allows XSS via a crafted HTML e-mail message.
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Analysis
by VulDB Data Team • 08/27/2022
The vulnerability identified as CVE-2022-36880 represents a cross-site scripting flaw within the Read Mail module of Webmin and Usermin software versions up to 1.995 and 1.850 respectively. This issue stems from inadequate input validation and output sanitization mechanisms that fail to properly handle maliciously crafted HTML content within email messages. The vulnerability exists in the way these web-based administration tools process and display email content, creating an avenue for attackers to inject malicious scripts that execute in the context of authenticated users' browsers.
The technical exploitation of this vulnerability occurs when a malicious email message containing crafted HTML content is delivered to a user's mailbox within the Webmin or Usermin interface. When the victim attempts to read the email through the vulnerable Read Mail module, the malicious HTML content is not properly sanitized before being rendered in the browser. This allows attackers to execute arbitrary JavaScript code within the victim's browser session, potentially leading to session hijacking, credential theft, or further compromise of the system. The vulnerability is particularly concerning because it operates within the context of authenticated users, meaning that successful exploitation requires no additional authentication beyond access to the email account.
From an operational impact perspective, this vulnerability exposes organizations to significant security risks as it can be leveraged for various malicious activities including but not limited to session theft, data exfiltration, and privilege escalation. The attack vector is relatively straightforward since it only requires sending a malicious email to a target user who has access to the Webmin or Usermin interface. The vulnerability affects both Webmin and Usermin products, which are widely used for web-based system administration, making the potential attack surface quite broad. Organizations using these tools may experience unauthorized access to sensitive system information and administrative functions, particularly when users are logged into these interfaces with elevated privileges.
The vulnerability maps to CWE-79 Cross-site Scripting and aligns with ATT&CK technique T1566.001 Phishing to achieve initial compromise. Mitigation strategies should include immediate patching of affected versions to version 1.996 for Webmin and 1.851 for Usermin, which contain proper input sanitization measures. Organizations should also implement additional security controls such as content security policies, regular security assessments of web-based administration tools, and user education regarding email security practices. Network-level protections including email filtering and web application firewalls can provide additional layers of defense. The vulnerability demonstrates the critical importance of proper input validation and output encoding in web applications, particularly in administrative interfaces where elevated privileges and sensitive data are handled. Regular security updates and vulnerability management processes are essential to prevent exploitation of such flaws in production environments.