CVE-2026-118573 in OAuth2 Token Manager
Summary
by MITRE • 10/30/2026
Missing Authorization vulnerability in Drupal OAuth2 Token Manager allows Forceful Browsing. This issue affects OAuth2 Token Manager versions: from 0.0.0 to 1.2.0.
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Analysis
by VulDB Data Team • 10/30/2026
The identified security flaw resides within the Drupal OAuth2 Token Manager module, specifically affecting version ranges from 0.0.0 through 1.2.0. This vulnerability is classified as a missing authorization check that enables forceful browsing, allowing unauthorized actors to access sensitive endpoints or data intended for authenticated users with specific privileges. In web application security, such flaws typically arise when the server-side logic fails to verify whether the requesting user possesses the necessary permissions before processing a request or returning information. This oversight creates a direct path for attackers to bypass authentication and authorization controls, effectively treating restricted resources as public assets accessible by any entity that can construct valid HTTP requests against the affected endpoints.
From a technical perspective, this vulnerability aligns with CWE-284, which describes Improper Access Control, specifically falling under the sub-category of insufficient verification of credentials or permissions during access to system resources. The core issue is not necessarily in the authentication mechanism itself but rather in the authorization layer that should validate user roles and scopes after a token has been presented. When an attacker interacts with the OAuth2 Token Manager API endpoints without proper scope validation, they can exploit this gap to retrieve tokens, view associated metadata, or manipulate session states intended for higher-privileged accounts. This type of flaw is particularly dangerous in authentication-centric modules because it undermines the fundamental trust model upon which secure identity management relies.
The operational impact of this vulnerability is significant due to its potential role as an initial access vector within a broader attack chain. An attacker leveraging forceful browsing against these endpoints could potentially harvest valid OAuth2 tokens, leading to account takeover or unauthorized data exfiltration depending on the scopes granted by those tokens. Furthermore, if the module handles sensitive configuration data related to third-party integrations, this exposure could reveal client secrets or redirect URIs, facilitating further phishing or man-in-the-middle attacks. The severity is compounded in environments where multiple users share access credentials or when automated systems rely heavily on these token endpoints for service-to-service communication without additional layering of security controls.
This behavior maps directly to the MITRE ATT&CK framework under technique T1078, specifically Valid Accounts and potentially T1528 Steal Application Access Token if the attacker successfully extracts active tokens from memory or database storage via these exposed endpoints. The lack of proper authorization checks allows adversaries to move laterally within an application by impersonating legitimate users who have already authenticated but whose session management is compromised through this flaw. In enterprise Drupal deployments, where integration with external identity providers and APIs is common, the exploitation of this vulnerability could lead to widespread compromise of connected services that trust the OAuth2 tokens issued or managed by the vulnerable module.
Mitigation strategies must prioritize immediate remediation for all systems running affected versions. The primary defense is upgrading the OAuth2 Token Manager module to a version greater than 1.2.0, where developers have presumably implemented robust authorization checks ensuring that only users with appropriate roles can access specific API endpoints. For organizations unable to upgrade immediately due to compatibility constraints or testing requirements, temporary mitigations should include implementing web application firewall rules that restrict access to the vulnerable endpoints based on IP reputation or behavioral anomalies. Additionally, administrators should enforce strict scope validation policies and ensure that token storage mechanisms are encrypted at rest to reduce the impact if tokens are inadvertently exposed through other vectors. Regular security audits focusing on authorization logic in authentication modules are recommended to prevent similar oversights in future development cycles.