Opencost Opencost vulnerabilities

OpenCost provides cost monitoring for Kubernetes workloads and cloud costs. Prior to 1.121.0, the POST /serviceKey endpoint in pkg/costmodel/router.go allows a network client to invoke AddServiceKey without mandatory authentication and submit an arbitrary key form value that is written to the GCP service-account key.json file returned by GetGCPAuthSecretFilePath in core/pkg/env/core.go. The attacker controls the file contents but not the CONFIG_PATH-derived directory, the key.json filename, or the file mode. Replacing the credential contents can disrupt GCP cost collection or cause OpenCost to use attacker-selected credentials, and the wildcard Access-Control-Allow-Origin response permits browser-assisted requests when the service is reachable from a browser. This issue is fixed in version 1.121.0.

OpenCost before 1.121.0 fails to authenticate the GET /helmValues endpoint, exposing base64-decoded HELM_VALUES environment variable containing cloud provider credentials. Additionally, adminAuthMiddleware fails open when ADMIN_TOKEN is unset, allowing unauthenticated attackers to modify GCP service account keys via POST /serviceKey to redirect billing calls.