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...

DEBIAN-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...

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...

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...

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...

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Duplicate Advisory This advisory has been withdrawn because it is a duplicate of GHSA-q5xf-xhwf-cwqf.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 (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...

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...

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...

The vulnerability of the oauth_verify_response() function in the flask_security/oauth_glue.py file, which is part of the Flask-Security-Too security management tool, allows a attacker to circumvent security restrictions.

The vulnerability of the oauthverifyresponse function in the flasksecurity/oauthglue.py file, a part of the Flask-Security-Too security management tool, is related to vulnerabilities in the authentication process. Exploiting this vulnerability could allow an attacker to circumvent security...

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-2026-47158: Cross-Site Request Forgery (CSRF)

Vaultwarden is a Bitwarden-compatible server written in Rust. Prior to 1.36.0, Vaultwarden's SSO authorization flow did not bind the OAuth state parameter accepted by /connect/authorize to the initiating browser session, allowed attacker-controlled PKCE parameters, and left SsoAuth records intact...

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...

EUVD-2026-43576

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...

PYSEC-2026-2730 Open WebUI: LDAP and OAuth First-User Race Condition Allows Multiple Admin Accounts

Summary The LDAP and OAuth authentication flows use a TOCTOU Time-of-Check-Time-of-Use pattern for first-user admin role assignment. The regular signup handler signuphandler in auths.py, line 663 was explicitly patched to prevent this race with the comment "Insert with default role first to avoid...

Open WebUI: LDAP and OAuth First-User Race Condition Allows Multiple Admin Accounts

SummaryThe LDAP and OAuth authentication flows use a TOCTOU Time-of-Check-Time-of-Use pattern for first-user admin role assignment. The regular signup handler signuphandler in auths.py, line 663 was explicitly patched to prevent this race with the comment "Insert with default role first to avoid...

FastMCP OAuth Proxy token reuse across MCP servers

While testing the OAuth Proxy implementation, it was noticed that the server does not properly respect the resource parameter submitted by the client in the authorization and token request. Instead of issuing the token explicitly for this MCP server, the token is issued for the baseurl passed to...