CVE-2026-91198 in GrowthBook
Summary
by MITRE • 09/15/2026
GrowthBook through 5.0.1 returns unredacted fact table definitions including raw warehouse SQL in payloads served by unauthenticated public report and experiment endpoints. Attackers with knowledge of a publicly shared report or experiment identifier can read internal data warehouse query text, schema, table names, filter values and datasource identifiers.
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Analysis
by VulDB Data Team • 09/15/2026
The vulnerability identified in GrowthBook versions up to 5.0.1 represents a critical information disclosure flaw within the application's public-facing API endpoints. Specifically, the unauthenticated report and experiment endpoints fail to properly sanitize or redact sensitive metadata associated with fact table definitions before returning them to the client. This architectural oversight allows any external actor who possesses knowledge of a publicly shared report identifier or experiment ID to retrieve detailed internal configurations that are intended for administrative use only. The core technical flaw lies in the serialization process where raw warehouse SQL queries, schema structures, and datasource identifiers are included directly in the response payload without adequate access control checks or data masking mechanisms. This indicates a failure in implementing the principle of least privilege regarding API responses, as sensitive backend configuration details are exposed to unauthenticated users who should only receive aggregated results or high-level experiment metrics.
From an operational perspective, this vulnerability enables attackers to conduct sophisticated reconnaissance against the organization's underlying data infrastructure. By extracting raw SQL queries and schema definitions, adversaries can map out the internal database structure, identifying critical tables, column names, and filtering logic used by the analytics platform. This information is invaluable for planning further attacks, such as targeted injection attempts or lateral movement within the network if other services share similar credentials or configurations. The exposure of datasource identifiers also reveals which data warehouses are integrated with GrowthBook, providing context about the organization's technology stack and potential attack surface expansion vectors. Furthermore, knowledge of filter values may allow attackers to infer sensitive business logic or proprietary algorithms that rely on specific data subsets for their calculations.
This issue aligns closely with CWE-200: Information Exposure, as it involves the unintentional leakage of information that could be detrimental to security posture. Additionally, the ability to enumerate internal structures and query patterns relates to CWE-1349: Insufficiently Protected Credentials in API Responses if those queries contain embedded authentication tokens or connection strings, although the primary impact here is structural reconnaissance. In terms of MITRE ATT&CK framework classification, this vulnerability facilitates the Discovery phase, specifically mapping to T1087: Account Discovery and potentially T1615: Indirect Command Execution if the exposed SQL can be manipulated in subsequent interactions with other vulnerable services. The lack of authentication requirements for these endpoints exacerbates the risk by removing a primary layer of defense that would otherwise restrict access to authorized personnel only.
Mitigation strategies must prioritize immediate remediation through software updates and configuration hardening. Organizations running GrowthBook versions 5.0.1 or earlier should upgrade to the latest patched version where this serialization issue has been resolved. Until an update is applied, administrators should ensure that report and experiment endpoints are not exposed directly to the public internet via reverse proxies or load balancers. Implementing strict access controls at the network level, such as IP whitelisting for administrative interfaces, can provide a temporary buffer against exploitation. Additionally, reviewing API response structures to ensure no sensitive backend metadata is serialized by default is essential for long-term security hygiene. Regular audits of public-facing endpoints should be conducted to verify that only necessary data points are returned and that all internal configuration details remain strictly within the authenticated admin context.