CVE-2008-6533 in Drupal
Summary
by MITRE
Drupal 5.x before 5.13 and 6.x before 6.7 does not delete all related content when an input format is deleted, which prevents the content from being properly filtered and allows remote attackers to conduct cross-site scripting (XSS) attacks via unspecified vectors.
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Analysis
by VulDB Data Team • 02/26/2025
The vulnerability identified as CVE-2008-6533 represents a critical security flaw in the Drupal content management system affecting versions 5.x prior to 5.13 and 6.x prior to 6.7. This issue stems from an improper handling of input format deletion processes within the Drupal framework, creating a persistent security gap that allows malicious actors to exploit cross-site scripting vulnerabilities. The flaw specifically manifests when administrators delete input formats from the system, yet fail to completely remove all associated content that was previously filtered through those formats.
The technical root cause of this vulnerability lies in the incomplete cleanup mechanism during input format deletion operations. When an input format is removed from Drupal's configuration, the system fails to properly traverse and eliminate all content items that were previously processed or filtered using that particular format. This incomplete removal creates a scenario where content remains accessible and executable within the system, despite the underlying filtering mechanism having been eliminated. The vulnerability is categorized under CWE-693, which specifically addresses protection mechanism failures in software systems, where the mechanism fails to provide the expected security protection.
The operational impact of CVE-2008-6533 is significant as it enables remote attackers to conduct cross-site scripting attacks through unspecified vectors that leverage the persistence of improperly cleaned content. Attackers can exploit this vulnerability by manipulating content that was originally filtered through deleted input formats, potentially allowing them to inject malicious scripts into web pages viewed by other users. This creates a persistent threat vector where malicious code can execute in the context of other users' browsers, potentially leading to session hijacking, data theft, or further system compromise. The vulnerability directly violates the principle of least privilege and proper resource cleanup, as the system fails to maintain proper isolation between different content filtering contexts.
The exploitation of this vulnerability aligns with ATT&CK technique T1059.001, which covers command and script injection methods, particularly focusing on cross-site scripting attacks. Security professionals should recognize this as a critical issue requiring immediate remediation, as it represents a fundamental flaw in Drupal's content management and security model. Organizations running affected Drupal versions face heightened risk of unauthorized code execution and user data compromise. The vulnerability demonstrates the importance of proper input validation and resource management in web applications, particularly in content management systems where user-generated content processing is a core function.
Mitigation strategies for CVE-2008-6533 require immediate implementation of the available security patches for Drupal 5.13 and 6.7, which address the incomplete cleanup mechanism during input format deletion. System administrators should conduct thorough audits of existing input formats and associated content to identify any remaining vulnerable elements. Additionally, organizations should implement proper content filtering policies and regularly review input format configurations to ensure that deleted formats are completely removed from system processing. The vulnerability highlights the necessity of maintaining robust security practices in web application development, particularly around resource cleanup and access control mechanisms. Regular security assessments and vulnerability scanning should be implemented to identify similar issues in other components of the Drupal ecosystem, as this flaw represents a broader pattern of incomplete security controls that can lead to persistent exploitation vectors.