The vulnerability arises when an attacker redirects a user to a malicious site that sends a POST request to the /api/job_agent/jobs/ endpoint on the Ray server. This endpoint, intended for internal use, lacks proper CSRF protections, allowing attackers to execute arbitrary code on the Ray cluster without the user's knowledge. The attack exploits the server's default configuration, which listens on all interfaces, thereby exposing it to the entire internal network. Additionally, the server reflects the Access-Control-Allow-Origin header from the request, enabling the attacker to bypass CORS policies and potentially read the response.

An attacker crafts a malicious website containing JavaScript code designed to send a POST request to the vulnerable Ray endpoint when visited by a user. The request includes a payload that executes arbitrary code on the Ray server. The user, upon visiting the attacker's website, unknowingly triggers the request, leading to unauthorized code execution on the Ray cluster. This scenario requires no further interaction from the user beyond visiting the malicious site.

Developers and organizations using Ray version 2.9.1, especially those running Ray clusters accessible within an internal network or on localhost, are vulnerable to this attack. The vulnerability can lead to unauthorized remote code execution, potentially compromising the security of the Ray cluster and the integrity of the organization's data and operations.