n8n before 2.30.1 and 2.29.8 assigns all Public API key scopes to JWTs issued through the Token Exchange module regardless of the acting user's role. On instances where the Token Exchange feature and Public API are enabled, a low-privileged user who can obtain a valid external JWT trusted by a configured issuer can use the resulting access token to invoke administrator-only Public API operations such as role escalation, user creation, and user deletion (role escalation requires an Advanced Permissions license), and, when unverified Community Package installation is enabled, achieve remote code execution.

n8n before 1.123.64, 2.x before 2.29.8, and before 2.30.1 contains a DOM-based cross-site scripting vulnerability in the HTML preview, which renders execution output into an iframe srcdoc without the sandbox attribute. A sanitizer bypass allows injected script to execute same-origin as the editor. When a victim opens the preview, the script can call authenticated APIs using the victim's session. An account with global:member privileges can exploit the issue.

n8n before 1.123.64, 2.29.8, and 2.30.1 contains a TOCTOU race condition in the Git node's clone operation that allows authenticated users to bypass path restrictions by swapping a directory for a symlink after the path is validated but before the clone runs. This lets an attacker plant a crafted repository in the community node directory, which n8n loads as a custom node on the next restart, executing arbitrary JavaScript on the server. Both self-hosted and cloud instances are affected.

n8n before 2.28.0 (and before 2.27.4 on the 2.27.x branch) registers the DELETE /${restEndpoint}/test-webhook/:id endpoint before authentication middleware is applied, allowing any unauthenticated network caller who knows a workflow ID to cancel that workflow's active test webhook registration. The impact is limited to disrupting in-progress test sessions; production webhooks, persistent workflow state, and stored data are not affected.

n8n before versions 1.123.61, 2.27.4, and 2.28.1 contains a permission bypass vulnerability in external secrets handling caused by a mismatch between the static validation check and the runtime expression engine. An authenticated user with credential create or update permissions but without the externalSecret:list scope can embed external secret references into credentials in forms the static validation does not detect; these references resolve at workflow execution time, exposing secret values the user is not authorized to access. This issue only affects instances where an external secrets provider is configured and Advanced Permissions are in use.

n8n before 2.28.1 contains an information disclosure vulnerability where external secrets are incorrectly resolved in workflow node expressions outside credentials scope. Authenticated project editors can read plaintext external secret values by referencing them in node expressions without requiring explicit secrets access permissions.

n8n before 2.19.3 contains a file path restriction bypass in the legacy ExecuteWorkflow node's localFile source option, which reads workflow files from disk without the file-access checks enforced by other file-reading nodes. Although hidden from the UI since v1.2, it remains reachable via the REST API. An authenticated user with permission to create or modify workflows can supply an arbitrary file path to bypass the N8N_RESTRICT_FILE_ACCESS_TO restriction and determine whether arbitrary files exist on the host; where the targeted path contains a valid workflow JSON file, that file can additionally be loaded and executed.

n8n before version 2.10.0 contains an input validation vulnerability in the Guardrail node that allows attackers to bypass default guardrail instructions. End users can craft malicious inputs to circumvent guardrail protections and compromise workflow integrity.

n8n contains an authentication bypass in the Chat Trigger node when configured with n8n User Auth (a non-default configuration). In affected releases — before 1.123.22, the 2.0.0 through 2.9.2 line, and 2.10.0 — the authentication check on the Chat Trigger webhook endpoint can be circumvented, allowing access without valid credentials. Fixed in 1.123.22, 2.9.3, and 2.10.1.

n8n before 1.123.24, 2.10.4, and 2.12.0 (across its 1.x and 2.x branches) contains cross-site scripting and open redirect vulnerabilities in the Form Node due to unsanitized HTML description fields and overly permissive iframe sandbox policies. Authenticated users with workflow creation permissions can inject malicious scripts or redirect parameters to perform stored XSS attacks or phishing redirects against end users.