CVE-2016-20001 in REST-JSON Project
Summary
by MITRE • 01/01/2021
The REST/JSON project 7.x-1.x for Drupal allows node access bypass, aka SA-CONTRIB-2016-033. NOTE: This project is not covered by Drupal's security advisory policy.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 09/06/2026
The vulnerability identified as SA-CONTRIB-2016-033 represents a critical authentication and authorization flaw within the REST/JSON module for Drupal version 7.x, specifically affecting development branches such as 7.x-1.x. This issue is classified under CWE-862, which denotes Missing Authorization, indicating that the application fails to enforce proper access controls on specific API endpoints or data structures exposed through its JSON interface. Unlike core Drupal security issues, this vulnerability resides in a contributed module and therefore falls outside the scope of standard Drupal security advisories, requiring administrators to rely on community reports and direct vendor communication for remediation guidance. The flaw allows an attacker to bypass node access permissions that are normally enforced by the CMS kernel, effectively granting unauthorized users read or write access to content they should not be able to view or modify based on their assigned roles and privileges.
From a technical perspective, the REST/JSON module serves as a bridge between Drupal’s internal data structures and external applications via Representational State Transfer protocols using JavaScript Object Notation payloads. The vulnerability likely stems from an incomplete implementation of access checking logic within the resource handlers that process incoming requests. When a request is received to retrieve or update node data, the module may fail to invoke the standard Drupal hook_node_access checks or similar permission verification mechanisms before returning the requested information. This oversight means that any user with valid credentials for the REST endpoint can potentially query nodes protected by strict access rules, such as those restricted to specific roles like administrators or editors only. The absence of these checks creates a direct path for data exfiltration without requiring privilege escalation beyond what is already granted to authenticated users interacting with the API.
The operational impact of this vulnerability is significant for organizations relying on Drupal’s REST services for mobile applications, third-party integrations, or headless CMS architectures. Attackers can exploit this flaw to harvest sensitive content, including personal identifiable information, confidential business documents, or proprietary data stored within restricted nodes. This leads directly to a compromise of confidentiality and potentially integrity if the module also allows write operations without proper authorization checks. In terms of cyber kill chain alignment, this vulnerability facilitates initial access and collection phases as defined by the MITRE ATT&CK framework, specifically mapping to techniques such as T1078 Valid Accounts for leveraging existing credentials and T1530 Data from Cloud Storage or Object Storage if the nodes contain file references. The ability to bypass node-level permissions undermines the fundamental security model of content management systems where granular access control is paramount.
Mitigation strategies must focus on immediate isolation and patching since this module is not covered by standard Drupal security updates. Administrators should immediately disable the REST/JSON module if it is not actively required for business operations, thereby removing the attack surface entirely. If the service is essential, organizations must apply any available patches provided by the project maintainers or consider migrating to a supported alternative that adheres to stricter security standards and receives regular audits. It is also advisable to implement network-level controls such as Web Application Firewalls configured with rulesets capable of detecting anomalous API behavior or unauthorized access patterns. Furthermore, conducting an audit of all exposed REST endpoints to ensure they enforce consistent authorization checks across the application stack can help prevent similar issues in other modules. Regular security assessments and penetration testing focused on API endpoints are recommended to identify any remaining gaps in access control logic before exploitation occurs.