CVE-2026-42809 - Stage-Create Credential Vending (pre-validation credential minting)🔗
Abstract🔗
An authenticated Apache Polaris user with permission to create a table can use a staged table creation request to obtain temporary storage credentials for any storage location reachable by the catalog’s configured role, regardless of whether they have permission to access that location. Polaris issues credentials before validating the requested location, allowing an attacker to target arbitrary storage paths including entire buckets.
Severity🔗
Important
Affected versions🔗
- Apache Polaris before 1.4.1
Description🔗
Apache Polaris can issue broad temporary (“vended”) storage credentials during staged table creation before the effective table location has been validated or durably reserved. Those temporary credentials are meant to limit the scope of accessible table data and metadata, but this scope limitation becomes attacker-directed because the attacker can choose a reachable target location.
In the confirmed variant, if the caller supplies a custom location during stage create and requests credential vending, Apache Polaris uses that location to construct delegated storage credentials immediately. The stage-create path itself neither runs the normal location validation nor the overlap checks before those credentials are issued.
Closely related to that, the staged-create flow also accepts write.data.path / write.metadata.path in the request properties and feeds those location overrides into the same effective table location set used for credential vending. Those fields are secondary to the main custom-location exploit, but they are still attacker-influenced location inputs that should be validated before any credentials are issued.