A bypass of n8n's SSRF protection allows an attacker who can create OAuth2 credentials to point the token exchange endpoint to an internal address. The resulting POST request runs from the n8n server to the target, and the response body is echoed back to the attacker, limited to what the target returns for that specific request. This flaw does not provide code execution but permits internal network reconnaissance or data exfiltration through crafted responses.

n8n-io n8n is affected for all releases prior to version 1.123.69 as well as the 2.x branch releases 2.33.4 and 2.34.1. Users on any of these versions that have permission to create OAuth2 credentials are impacted.

The CVSS score of 2.3 indicates low severity, and there is no EPSS data or KEV listing, suggesting limited public exploitation. The likely attack vector is internal network reachability from the n8n instance; an attacker needs credential-creation privileges, which may be limited to administrators. The vulnerability can be leveraged to trick the server into making requests within its own network and expose the response payload, but it does not allow arbitrary code execution or full control over the system.