n8n is an open source workflow automation platform. Prior to versions 1.123.32, 2.17.4, and 2.18.1, an authenticated user with a valid API key scoped to variable:list could read variables from projects they are not a member of by supplying an arbitrary projectId query parameter to the public API variables endpoint. The handler queried the variables repository directly without enforcing project membership checks, bypassing the authorization-aware service layer used by the internal enterprise controller. If variables were misused to store sensitive information such as credentials or tokens, they should be rotated immediately. This issue only affects licensed enterprise or team deployments with multiple projects and the variables feature enabled. This issue has been patched in versions 1.123.32, 2.17.4, and 2.18.1.
Weakness
The system’s authorization functionality does not prevent one user from gaining access to another user’s data or record by modifying the key value identifying the data.
Affected Software
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| N8n | N8n | * | 1.123.32 (excluding) |
| N8n | N8n | 2.17.0 (including) | 2.17.4 (excluding) |
| N8n | N8n | 2.18.0 (including) | 2.18.0 (including) |
Extended Description
Retrieval of a user record occurs in the system based on some key value that is under user control. The key would typically identify a user-related record stored in the system and would be used to lookup that record for presentation to the user. It is likely that an attacker would have to be an authenticated user in the system. However, the authorization process would not properly check the data access operation to ensure that the authenticated user performing the operation has sufficient entitlements to perform the requested data access, hence bypassing any other authorization checks present in the system. For example, attackers can look at places where user specific data is retrieved (e.g. search screens) and determine whether the key for the item being looked up is controllable externally. The key may be a hidden field in the HTML form field, might be passed as a URL parameter or as an unencrypted cookie variable, then in each of these cases it will be possible to tamper with the key value. One manifestation of this weakness is when a system uses sequential or otherwise easily-guessable session IDs that would allow one user to easily switch to another user’s session and read/modify their data.