Loading vulnerability…
Authentication Bypass in Flowise OAuth2 Credential Refresh Endpoint
CVE-2026-70636 is an authentication and authorization bypass vulnerability in Flowise through version 3.1.4 affecting the OAuth2 credential refresh functionality. The flaw stems from prefix-based whitelist matching in the authentication middleware, where the OAuth2 credential refresh route is treated as globally whitelisted and excluded from normal API key and JWT enforcement. By sending a crafted POST request to the OAuth2 credential refresh route with a trailing credential identifier, an unauthenticated attacker can reach the refresh handler without passing authentication checks. The handler then loads credentials by identifier, decrypts the stored OAuth material, performs a token refresh operation, and updates the stored credential record without verifying caller identity, workspace ownership, or role-based authorization. This results in unauthorized cross-workspace manipulation of OAuth credential state and is described as a bypass of the earlier CVE-2026-41273 remediation.
What it means and what to do now: patch path, interim mitigations, and the assume-compromise checklist.
What an attacker gets, and what they’ve been doing with it.
Successful exploitation allows an unauthenticated attacker to trigger OAuth token refresh operations for credentials associated with other workspaces. The primary impact is integrity compromise through unauthorized mutation and rotation of stored OAuth credential state, including cross-workspace credential lifecycle manipulation and bypass of workspace isolation boundaries. This can disrupt dependent OAuth integrations and operational workflows that rely on those credentials. Available information indicates the refreshed access tokens are not directly disclosed to the attacker, so the impact is primarily unauthorized state change rather than direct token theft.
If you can’t patch tonight, do this now.
Until a fixed release is deployed, restrict external access to Flowise instances, especially any API routes related to OAuth credential management. Require access through trusted network boundaries or an authenticated reverse proxy, and disable or tightly control use of the OAuth2 credential refresh functionality where feasible. Monitor for unexpected OAuth credential refresh activity and unauthorized credential state changes across workspaces. Review and harden any route-whitelisting logic to prevent prefix-based authentication bypass conditions.
Patch, then assume compromise.
Upgrade Flowise to a fixed version newer than 3.1.4 that corrects the authentication middleware behavior and removes the OAuth2 credential refresh endpoint from unauthenticated whitelist handling. A complete fix should ensure the refresh endpoint always requires authenticated access, enforce authorization checks before loading or mutating credentials, validate workspace ownership or tenancy boundaries for the referenced credential, and apply RBAC controls to refresh operations. Prefix-based whitelist logic should be audited and replaced or constrained so route matching cannot be abused with attacker-controlled path suffixes.
No public exploits tracked yet. Mallory keeps watching.
Products and vendors Mallory has correlated with this vulnerability. Open in Mallory to drill down to specific CPE configurations and version ranges.
6 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.