CVE-2026-42812: In Apache Iceberg, the table's metadata files are control files: they tell readers which data files belong to the table and which table version to read…

PriorityP263critical9.9CVSS 3.1

AVNACLPRLUINSCCHIHAH

EPSS

0.36%

28.3th percentile

In Apache Iceberg, the table's metadata files are control files: they tell readers which data files belong to the table and which table version to read. `write.metadata.path` is an optional table property that tells Polaris where to write those metadata files. For a table already registered in a Polaris-managed catalog, changing only that property through an `ALTER TABLE`-style settings change (not a row-level `INSERT`, `SELECT`, `UPDATE`, or `DELETE`) bypasses the commit-time branch that is supposed to revalidate storage locations. The full persisted / credential-vending variant requires the affected catalog to have `polaris.config.allow.unstructured.table.location=true`, with `allowedLocations` broad enough to include the attacker-chosen target. `allowedLocations` is the admin-configured allowlist of storage paths that the catalog is allowed to use. Public project materials suggest that this flag is a real supported compatibility / layout mode, not just a contrived lab-only prerequisite. In that configuration, a user who can change table settings can cause Apache Polaris itself to write new table metadata to an attacker-chosen reachable storage location before the intended location-validation branch runs. If the later concrete-path validation also accepts that location, Polaris persists the resulting metadata path into stored table state. Later table-load and credential APIs can then return temporary cloud-storage credentials for the same location without revalidating it. In plain terms, Polaris can later hand out temporary storage access for the same attacker-chosen area. That attacker-chosen area does not need to be limited to the poisoned table's own files. If it is a broader storage prefix, another table's prefix, or, depending on configuration or provider behavior, even a bucket/container root, the resulting disclosure or corruption scope can extend to any data and metadata Polaris can reach there. The practical consequences are therefore similar t

Affected

2 ranges

Vendor	Product	Version range	Fixed in
apache	polaris	< 1.4.1	1.4.1
apache_software_foundation	apache_polaris	< 1.4.1	1.4.1

CVSS provenance

nvdv3.19.9CRITICALCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

nvdv4.09.4CRITICALCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

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