GHSA-fxcw-h3qj-8m8p: n8n Has External Secrets Authorization Bypass in Credential Saving

n8n, a workflow automation tool, had a security flaw where authenticated users without permission could bypass authorization checks and access plaintext values of external secrets (credentials stored in connected vaults) by guessing secret names. This vulnerability only affects instances with external vaults configured and requires the attacker to be a valid user who knows the target secret's name.