Which versions of Flowise are affected by CVE-2026-56270?

FlowiseAI Flowise versions 3.0.13 and earlier contain an unauthenticated vulnerability exposing cleartext OAuth secrets for Google, Microsoft/Azure, GitHub, and Auth0 through a single GET request.. A patch is available.

Is there a public PoC exploit available for CVE-2026-56270?

Yes, a public proof-of-concept exploit is available for CVE-2026-56270. Prioritise patching immediately. EPSS: 0.4%.

How to fix or mitigate CVE-2026-56270?

Within 24 hours: inventory all Flowise deployments and confirm version; if running 3.0.13 or earlier, immediately restrict network access to /api/v1/loginmethod endpoint and review access logs for exploitation. Within 7 days: contact FlowiseAI for patch timeline; deploy Web Application Firewall rules blocking the vulnerable endpoint from untrusted networks; require IP whitelisting for any remaining Flowise access. Within 30 days: apply vendor patch immediately upon release; rotate all OAuth secrets in Google Cloud Console, Azure AD, GitHub OAuth settings, and Auth0 tenant; audit authentication logs for unauthorized SSO events.

Flowise CVE-2026-56270

Q: What is the CVSS score of CVE-2026-56270?

CVE-2026-56270 has a CVSS 4.0 base score of 8.7 (High). CVSS vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X. EPSS exploitation probability: 0.4%.

EUVD-2026-38747 HIGH

Missing Authentication for Critical Function (CWE-306)

2026-06-24 VulnCheck

Authentication Bypass Microsoft Google Flowise

8.7

CVSS 4.0 · Vendor: VulnCheck

Severity by source

Vendor (VulnCheck) PRIMARY

8.7 HIGH

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

vuln.today AI

7.5 HIGH

Unauthenticated remote GET on a default endpoint (AV:N/AC:L/PR:N/UI:N); pure secret disclosure with no integrity or availability impact, so C:H, I:N, A:N.

3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N

Primary rating from Vendor (VulnCheck).

CVSS VectorVendor: VulnCheck

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Lifecycle Timeline

Patch available

Jun 24, 2026 - 13:01 EUVD

Source Code Evidence Fetched

Jun 24, 2026 - 12:20 vuln.today

Analysis Generated

Jun 24, 2026 - 12:20 vuln.today

CVE Published

Jun 24, 2026 - 11:53 cve.org

HIGH 8.7

DescriptionCVE.org

Flowise before 3.1.0 (versions 3.0.13 and earlier) contains a missing authentication vulnerability in the /api/v1/loginmethod endpoint that allows unauthenticated users to retrieve an organization's complete SSO configuration, including OAuth client secrets in cleartext, by providing an organizationId parameter. Remote attackers can send a GET request to harvest sensitive API credentials for Google, Microsoft/Azure, GitHub, and Auth0 integrations. This affects FlowiseAI Cloud and self-hosted instances where the endpoint is exposed.

AnalysisAI

Unauthenticated OAuth secret disclosure in FlowiseAI Flowise versions 3.0.13 and earlier allows remote attackers to harvest cleartext SSO client secrets for Google, Microsoft/Azure, GitHub, and Auth0 by sending a single GET request to /api/v1/loginmethod with a guessable organizationId. Affects both FlowiseAI Cloud and self-hosted deployments where the endpoint is reachable; publicly available exploit code exists (vendor GHSA includes a complete request/response PoC), and the leaked credentials enable downstream identity-provider compromise.

Technical ContextAI

Flowise is an open-source low-code platform (npm package 'flowise') for building LLM/agent workflows; FlowiseAI also runs a managed Cloud edition. The /api/v1/loginmethod REST endpoint is intended to return SSO provider metadata for a tenant so the login UI can render the correct OAuth buttons. The root cause is CWE-306 (Missing Authentication for Critical Function): the handler accepts an organizationId query parameter and returns the full providers configuration record from the database - including the OAuth clientSecret field stored in cleartext - without verifying any session, API key, or tenant membership. Per the CPE 'cpe:2.3:a:flowise:flowise:*' and the npm 'flowise' package metadata, all versions up to and including 3.0.13 ship this endpoint without an auth guard.

RemediationAI

Vendor-released patch: Flowise 3.1.0 - upgrade the 'flowise' npm package to 3.1.0 or later immediately (see https://github.com/FlowiseAI/Flowise/security/advisories/GHSA-6pcv-j4jx-m4vx). Because the disclosed OAuth client secrets must be assumed compromised, after upgrading you should rotate every clientSecret configured under SSO providers (Google, Microsoft/Azure, GitHub, Auth0) in both Flowise and the respective identity provider consoles, and review IdP audit logs for unexpected token issuance. If immediate upgrade is not possible, compensating controls include blocking or rate-limiting /api/v1/loginmethod at an upstream reverse proxy or WAF (side effect: the login page may fail to render SSO buttons for unauthenticated visitors, so users must know the direct provider URL), restricting Flowise to a trusted network or VPN until patched, and temporarily disabling SSO providers in Flowise so no secrets are stored in the leaked record.