CVE-2015-8081 in Field as Block Module
Summary
by MITRE
The Field as Block module 7.x-1.x before 7.x-1.4 for Drupal might allow remote attackers to obtain sensitive field information by reading a cached block.
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Analysis
by VulDB Data Team • 03/08/2018
The vulnerability identified as CVE-2015-8081 affects the Field as Block module version 7.x-1.x prior to 7.x-1.4 within the Drupal content management system. This security flaw represents a significant information disclosure risk that could potentially expose sensitive field data to unauthorized remote attackers. The vulnerability specifically manifests when the module processes cached block data, creating an avenue for attackers to access field configuration information that should remain protected.
The technical implementation of this vulnerability stems from inadequate access control mechanisms within the Field as Block module's caching system. When blocks are generated and cached, the module fails to properly validate whether the requesting user should have access to the underlying field information. This design flaw allows remote attackers to exploit the cached block functionality and retrieve field definitions, field types, and potentially other sensitive metadata that would normally be restricted based on user permissions. The issue occurs during the block rendering process where cached data is served without proper authorization checks, creating a path for information leakage.
The operational impact of this vulnerability extends beyond simple information disclosure, as field information can contain sensitive configuration details that might aid attackers in planning more sophisticated attacks. The cached nature of the vulnerability means that even if access controls are properly enforced at the time of block generation, the cached data remains accessible to unauthorized users. This creates a persistent risk where previously cached field information can be retrieved by any remote attacker who can access the cached block endpoints. The vulnerability affects Drupal 7.x installations where the Field as Block module is enabled, potentially compromising the confidentiality of field-level data across multiple sites.
Mitigation strategies for CVE-2015-8081 should prioritize immediate patching to version 7.x-1.4 or later of the Field as Block module. Organizations should also implement additional security controls including restricting access to cached block endpoints through web server configuration, implementing proper content delivery network security measures, and conducting comprehensive security audits of all Drupal modules. The vulnerability aligns with CWE-200, Information Exposure, and represents a clear violation of the principle of least privilege in access control. From an ATT&CK framework perspective, this vulnerability maps to T1083 (File and Directory Discovery) and T1566 (Phishing), as it enables attackers to gather information that could facilitate further exploitation. System administrators should also consider implementing monitoring solutions to detect unusual access patterns to cached block resources and establish regular security assessments to identify similar vulnerabilities in other modules. The incident underscores the importance of proper input validation and access control implementation in web applications, particularly when dealing with cached data that may contain sensitive information.