CVE-2026-73407 in Budibase
Summary
by MITRE • 08/12/2026
Budibase is an open-source low-code platform. Prior to 3.40.1, RestIntegration._req in packages/server/src/integrations/rest.ts attached credentials from getAuthHeaders and defaultHeaders without requiring the final request destination to match the datasource origin. An unauthenticated caller of a PUBLIC POST /api/v2/queries/:queryId query could supply an absolute or parameterized path to an attacker-controlled host and receive the stored bearer, basic, or static-header credentials. This issue is fixed in version 3.40.1.
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Analysis
by VulDB Data Team • 08/12/2026
The vulnerability identified in Budibase versions prior to 3.40.1 represents a critical authorization bypass flaw that undermines the security of the platform's integration capabilities. This issue specifically affects the RestIntegration._req function located in packages/server/src/integrations/rest.ts, which handles HTTP requests for REST API integrations within the low-code platform. The vulnerability stems from insufficient validation of request destinations, allowing attackers to manipulate the final request path to point to arbitrary external hosts while still leveraging stored authentication credentials that were meant to be restricted to specific data source origins.
The technical flaw manifests in how the system processes authentication headers and default headers during REST integration requests. When a user configures a datasource with authentication credentials such as bearer tokens, basic authentication headers, or static headers, these credentials are properly stored within the system. However, the RestIntegration._req function fails to validate whether the final destination of the HTTP request matches the original data source origin that provided the credentials. This validation gap occurs because the system does not enforce hostname or domain restrictions on where credentials can be used, creating a path traversal-like scenario where attacker-controlled paths can utilize legitimate authentication information.
The operational impact of this vulnerability is severe and affects any unauthenticated user who can access public POST endpoints within the platform's API. Specifically, callers to the PUBLIC POST /api/v2/queries/:queryId endpoint can craft malicious requests that specify absolute or parameterized paths pointing to attacker-controlled hosts. When such requests are processed, the system automatically appends the stored authentication credentials from getAuthHeaders and defaultHeaders without proper origin validation. This means that an attacker could potentially escalate privileges by using legitimate authentication tokens to access resources on external systems, effectively bypassing the intended security boundaries of the platform's integration architecture.
This vulnerability aligns with several cybersecurity frameworks and threat models, particularly CWE-285 which addresses improper authorization in software systems, and CWE-346 which covers "Origin Validation Error" where applications fail to validate that data originates from a trusted source. The issue also maps to ATT&CK technique T1078.004 which covers legitimate credentials for privilege escalation, as attackers can leverage stored authentication tokens to gain unauthorized access to external systems. Additionally, this vulnerability demonstrates characteristics of path traversal and injection attacks where the system fails to properly validate input paths against expected origins.
The fix implemented in version 3.40.1 addresses this issue by introducing proper validation of request destinations against the original data source origins. This mitigation ensures that authentication credentials are only attached to requests that match the configured datasource domains, preventing credential leakage to attacker-controlled hosts. Organizations using affected versions should immediately upgrade to 3.40.1 or later to protect against potential exploitation of this vulnerability. Security teams should also review existing integration configurations and monitor for any unauthorized access attempts that might indicate exploitation of this vulnerability. The fix represents a fundamental improvement in the platform's authorization model, ensuring that stored credentials remain bound to their intended origins while maintaining the platform's legitimate integration functionality.