TensorZero is an open-source LLMOps platform that unifies an LLM gateway, observability, evaluation, optimization, and experimentation. Prior to 2026.6.0, the TensorZero Gateway /internal/object_storage endpoint accepts a caller-supplied JSON storage_path parameter that dynamically overrides the [object_storage] configuration. Selecting the filesystem storage type allows arbitrary files on the gateway filesystem to be read, including credential files. Selecting the s3_compatible storage type causes outbound object-storage requests to attacker-chosen internal or cloud-metadata endpoints. Exploitation requires access to the gateway, which can be authenticated or unauthenticated depending on deployment configuration. This issue is fixed in version 2026.6.0.