The vulnerability is a server-side request forgery that allows an attacker to instruct the Kubeflow Pipelines frontend to fetch arbitrary HTTP or HTTPS resources. When the source URL includes an all‑digit decimal host, the URL parser interprets it as an IPv4 address, bypassing the bucket validator. This flaw lets an unauthenticated user retrieve the response body from internal endpoints, potentially leaking sensitive information. In a multi‑user configuration, a low‑privilege tenant with a valid identity can also trigger the same path, exposing internal resources or, if service metadata providers are reachable, cloud credentials. The upper‑layer CWE involved is 918, indicating an SSRF weakness that can compromise confidentiality and availability.

Kubeflow Pipelines versions prior to 2.18.0 are affected. The flaw exists in the frontend GET /artifacts/get route, especially when using the default ALLOWED_ARTIFACT_DOMAIN_REGEX and when authentication is disabled or misconfigured. The issue was fixed in the 2.18.0 release.

With a CVSS score of 8.6, this vulnerability is considered high severity. EPSS data is not available, but the complexity of the attack does not require special skills; an unauthenticated or low‑privileged user can trigger the request. Because the flaw allows leakage of internal or cloud metadata, the potential impact to confidentiality could be significant. The CWE‑918 identification highlights that proper input validation is missing, making the vulnerability readily exploitable. No KEV tagging indicates it has not been identified as a known exploited vulnerability yet, but its high score warrants prompt mitigation.