n8n: Member-Level Users Can Execute Other Users' MCP Server Trigger Workflows via Missing OAuth Authorization Check

Impact The OAuth 2.1 consent and token-issuance flow introduced in n8n 2.27.0 does not verify that the authenticated user has access to the workflow referenced as the OAuth resource. A member-level user can register an OAuth client, self-approve consent for another user's n8n OAuth2-protected MCP...

CVE-2026-16615

A flaw was found in librest. The PKCE implementation for OAuth authorization uses the GRand function from the GLib API, a cryptographically insecure pseudo-random number generator. Because the generated "code verifier" lacks sufficient cryptographic entropy, a malicious actor can reverse-engineer...

EUVD-2026-47742

A flaw was found in librest. The PKCE implementation for OAuth authorization uses the GRand function from the GLib API, a cryptographically insecure pseudo-random number generator. Because the generated "code verifier" lacks sufficient cryptographic entropy, a malicious actor can reverse-engineer...

Duplicate Advisory: Member-Level Users Can Execute Other Users' MCP Server Trigger Workflows via Missing OAuth Authorization Check

Duplicate Advisory This advisory has been withdrawn because it is a duplicate of GHSA-q5xf-xhwf-cwqf. This link is maintained to preserve external references. Original Description n8n before 2.29.8 and 2.30.x before 2.30.1 affected from 2.27.0, when the OAuth 2.1 consent and token-issuance flow w...

CVE-2026-65594 n8n before 2.30.1 Missing OAuth Authorization Check

n8n before 2.29.8 and 2.30.x before 2.30.1 affected from 2.27.0, when the OAuth 2.1 consent and token-issuance flow was introduced does not verify that the authenticated user has access to the workflow referenced as the OAuth resource. On instances with at least one active MCP Server Trigger...

CVE-2026-65594

n8n (versions affected: before 2.29.8 and 2.30.x before 2.30.1; affected since 2.27.0) has an OAuth 2.1 flow where authentication does not verify that the user has access to the referenced workflow used as the OAuth resource. On systems with an active MCP Server Trigger workflow configured for n8...

EUVD-2026-47638

n8n before 2.29.8 and 2.30.x before 2.30.1 affected from 2.27.0, when the OAuth 2.1 consent and token-issuance flow was introduced does not verify that the authenticated user has access to the workflow referenced as the OAuth resource. On instances with at least one active MCP Server Trigger...

CVE-2026-46715 Flask-Security-Too OAuth reauthentication freshness bypass via cross- user OAuth identity acceptance

Flask-Security-Too allows users to add security features to their Flask applicationa. Version 5.8.0's OAuth reauthentication flow can mark a session as fresh after verifying an OAuth account that belongs to a different user. If an attacker can operate an already-authenticated but stale victim...

CVE-2026-16089

A flaw was found in the keycloak-services component of Red Hat Build of Keycloak. The issue occurs because OAuth 2.0 authorization codes are not properly bound to the client that originally requested them. An attacker who can intercept an authorization code can modify it to be redeemed by their o...

CVE-2026-58489

HedgeDoc is an open source, real-time collaborative markdown notes application. Prior to 1.11.0, the GitHub Gist export flow created an OAuth2 state value but only checked that it was present rather than validating it against the value expected for the user's session. Because the state was not...

CVE-2026-58489

HedgeDoc is an open source, real-time collaborative markdown notes application. Prior to 1.11.0, the GitHub Gist export flow created an OAuth2 state value but only checked that it was present rather than validating it against the value expected for the user's session. Because the state was not...

PT-2026-57920

Name of the Vulnerable Software and Affected Versions HedgeDoc versions prior to 1.11.0 Description The GitHub Gist export flow fails to properly validate the OAuth2 state value, checking only for its presence instead of verifying it against the user session. This allows an attacker to forge a...

CVE-2026-55672 ZITADEL: Missing client_id binding in OIDC authorization code exchange and refresh token flows (RFC 6749 Section 4.1.3 violation)

ZITADEL is an open source identity management platform. Prior to 3.4.12 and 4.15.2, ZITADEL's OAuth2 and OIDC CodeExchange, RefreshToken, and device token flows fail to verify that the requesting client matches the client that initiated the authorization flow, allowing intercepted grants or refre...

PT-2026-52592

Name of the Vulnerable Software and Affected Versions Keycloak affected versions not specified Description A JWT algorithm confusion flaw exists in the JWT Authorization Grant flow. An attacker possessing valid client credentials can bypass signature verification by forging an assertion. This...

CVE-2026-55666

Rocket.Chat is an open-source, secure, fully customizable communications platform. Prior to 8.5.1, 8.4.4, 8.3.6, 8.2.6, 8.1.6, 8.0.7, and 7.10.13, in apps/meteor/app/apple/server/loginHandler.ts, handleIdentityToken parses a JWT issued by Apple during the OAuth flow. The try block checks for an...

CVE-2026-54305

CVE-2026-54305 affects n8n Enterprise instances using the Dynamic Credentials EE Endpoints. Prior to versions 1.123.55, 2.25.7, and 2.26.2, three Dynamic Credentials endpoints accepted any authenticated session without per-resource ownership or scope checks on the target workflow or credential. A...

CVE-2026-56425

The Azure Active Directory AAD authentication implementation contained multiple weaknesses in its OAuth 2.0 authorization flow that could allow attackers to bypass important security guarantees provided by the protocol. The application used the PHP session identifier sessionid as the OAuth state...

CVE-2026-56425 MISP AAD authentication plugin - Improper OAuth State Handling, Missing Session Rotation, Insecure Redirect URI Validation, and Log Injection

The Azure Active Directory AAD authentication implementation contained multiple weaknesses in its OAuth 2.0 authorization flow that could allow attackers to bypass important security guarantees provided by the protocol. The application used the PHP session identifier sessionid as the OAuth state...

CVE-2026-48991

XianYuLauncher (Minecraft Java Edition launcher) is affected in versions prior to 1.5.5. The legacy Microsoft account OAuth sign-in flow used a fixed localhost redirect URI and lacked PKCE and state validation, allowing sensitive authentication artifacts to be exposed under certain local attack c...

GHSA-2J5H-858J-5MPF n8n: Cross-Tenant Credential Takeover via Dynamic Credentials EE Endpoints

Impact Three EE endpoints used by the Dynamic Credentials feature accepted any authenticated n8n session without performing per-resource ownership or scope checks on the target workflow or credential. An authenticated user with no project membership or credential sharing relationship could...