CVE-2012-1503 in Movable Type
Summary
by MITRE
Cross-site scripting (XSS) vulnerability in Six Apart (formerly Six Apart KK) Movable Type (MT) Pro 5.13 allows remote attackers to inject arbitrary web script or HTML via the comment section.
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Analysis
by VulDB Data Team • 01/26/2025
The vulnerability identified as CVE-2012-1503 represents a critical cross-site scripting flaw within Six Apart's Movable Type Pro 5.13 content management system. This security weakness resides in the comment section processing functionality, creating an avenue for remote attackers to execute malicious web scripts or HTML code within the context of affected user sessions. The vulnerability stems from insufficient input validation and output sanitization mechanisms that fail to properly escape or filter user-supplied data before rendering it in web pages.
The technical exploitation of this XSS vulnerability occurs when malicious actors submit crafted payloads through the comment submission interface. These payloads typically contain javascript code or html elements that get executed when other users view the affected comments. The flaw falls under CWE-79 which categorizes improper neutralization of input during web page generation, specifically addressing the failure to sanitize user-controllable data before incorporating it into dynamically generated web content. This vulnerability enables attackers to perform session hijacking, defacement of web pages, and potentially execute unauthorized actions on behalf of authenticated users.
The operational impact of CVE-2012-1503 extends beyond simple data corruption or display manipulation. Attackers can leverage this vulnerability to steal session cookies, redirect users to malicious sites, inject phishing content, or perform actions that compromise the integrity of the content management system. When combined with other exploitation techniques, this XSS vulnerability can serve as a launching point for more sophisticated attacks targeting the underlying web application infrastructure. The vulnerability particularly affects organizations using Movable Type Pro 5.13 for collaborative content management where user comments are enabled, creating a persistent threat vector that can remain active as long as the vulnerable version remains deployed.
Mitigation strategies for this vulnerability center on immediate patch application from Six Apart, as the vendor would have released a security update addressing the input validation gaps in the comment processing module. Organizations should implement comprehensive input sanitization measures including the use of content security policies, proper HTML escaping of user inputs, and regular security audits of web applications. The ATT&CK framework categorizes this vulnerability under the 'Web Application Attack' domain, specifically relating to techniques involving client-side code injection and session management compromise. Additionally, implementing web application firewalls and monitoring for suspicious comment patterns can provide defensive layers while awaiting official patches, though these measures should not be considered substitutes for proper software updates and security hardening practices.