CVE-2011-0707 in Mailman
Summary
by MITRE
Multiple cross-site scripting (XSS) vulnerabilities in Cgi/confirm.py in GNU Mailman 2.1.14 and earlier allow remote attackers to inject arbitrary web script or HTML via the (1) full name or (2) username field in a confirmation message.
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Analysis
by VulDB Data Team • 10/17/2021
The vulnerability identified as CVE-2011-0707 represents a critical cross-site scripting weakness in GNU Mailman version 2.1.14 and earlier systems. This flaw exists within the Cgi/confirm.py script which processes confirmation messages for mailing list subscriptions and management. The vulnerability stems from inadequate input validation and sanitization mechanisms that fail to properly escape or filter user-supplied data before rendering it in web responses. Attackers can exploit this weakness by crafting malicious payloads in either the full name or username fields of confirmation messages, which are then executed in the context of other users' browsers when they view these confirmation pages.
The technical exploitation of this vulnerability occurs through the manipulation of web input fields that are not adequately sanitized before being incorporated into HTML output. When users submit confirmation requests containing malicious script code in the full name or username fields, the vulnerable Mailman application stores this data without proper encoding or filtering. Subsequently, when other users access the confirmation pages, the stored malicious content is executed in their browsers, potentially leading to session hijacking, credential theft, or redirection to malicious sites. This vulnerability aligns with CWE-79 which specifically addresses cross-site scripting flaws in web applications, and represents a classic example of reflected XSS where user input is directly reflected back in application responses without proper sanitization.
The operational impact of CVE-2011-0707 extends beyond simple script execution as it can enable sophisticated attack vectors within mailing list environments. An attacker could craft confirmation messages that redirect users to phishing sites, steal session cookies, or inject malicious content that persists across multiple user interactions. Given that mailing lists often contain sensitive organizational communications and personal information, the potential for data exfiltration or unauthorized access increases significantly. The vulnerability is particularly concerning in enterprise environments where Mailman serves as a primary communication platform, as it could compromise the security of entire mailing list ecosystems and potentially provide attackers with access to privileged user information.
Mitigation strategies for this vulnerability must address both immediate remediation and long-term security hardening of the Mailman installation. The most effective immediate solution involves upgrading to GNU Mailman version 2.1.15 or later where the XSS vulnerabilities have been patched through proper input validation and output encoding mechanisms. Organizations should implement comprehensive input sanitization routines that escape special characters in all user-supplied fields, particularly those that appear in web interfaces. Additionally, implementing Content Security Policy headers can provide an additional layer of protection against XSS attacks by restricting the sources from which scripts can be loaded. Security practitioners should also consider deploying web application firewalls that can detect and block suspicious input patterns targeting known XSS vulnerabilities. The remediation process should include thorough testing of all user-facing interfaces to ensure that no other input fields are susceptible to similar vulnerabilities, aligning with ATT&CK technique T1213 which addresses credential access through web application attacks. Regular security audits and input validation reviews should be implemented to prevent similar vulnerabilities from emerging in future releases.