High · published September 29, 2026
Apache Polaris allows an authenticated principal with permission to create or update Iceberg table properties to set FileIO client settings such as s3.endpoint in table metadata.
In versions < 1.8.0, when Polaris performs server-side Iceberg operations, including commits and purges, it may use those settings to construct its (server-side) FileIO client. If the catalog storage configuration does not override the endpoint, Polaris can send storage requests to a host chosen by the table writer, using credentials scoped to the operation.
This can redirect server-side storage traffic and expose request authentication material to the chosen endpoint. Deployments are affected when table writers are not trusted to configure server-side storage endpoints.