CVE-2026-42811
CriticalCVSS 9.9Exploitation Probability (EPSS)
Low risk37th percentile - higher than 37% of all known CVEs
Summary
Apache Polaris issues short-lived GCS credentials with a CEL-based path restriction built without escaping the namespace or table identifier. A crafted identifier containing a single quote and CEL fragments can break out of the quoted string and broaden the credentials to the entire configured bucket. This was confirmed in testing against Polaris 1.4.0 with real Google Cloud Storage.
Risk Assessment
Credentials issued for one table may allow listing, reading, creating, and deleting objects of other tables and unrelated prefixes within the same bucket. This breaks data isolation and creates a risk of unauthorized access or modification of data in GCS.
Recommendation
Update Apache Polaris to a version that properly escapes identifiers in CEL expressions. Until patched, restrict namespace and table creation to trusted users and apply least-privilege RBAC for Polaris principals.
Other vulnerabilities in Apache Polaris
See all- CVE-2026-42812Critical
Apache Polaris contains a vulnerability allowing a user who can change table settings to bypass storage location validation during metadata writes. Changing only the `write.metadata.path` property via an `ALTER TABLE`-style change skips the commit-time validation branch, potentially causing Polaris to write metadata to an attacker-chosen location and later vend credentials for that location.
- CVE-2026-42810Critical
Apache Polaris accepts literal `*` characters in namespace and table names and later reuses them unescaped in S3 IAM resource patterns and `s3:prefix` conditions. Because `*` acts as a wildcard in S3 IAM policy matching, temporary credentials issued for a crafted table (e.g. `f*.t1`, `*.*`) can match the storage path of a different table. Confirmed behavior includes reading another table's Iceberg metadata JSON, listing its exact S3 prefix, and creating or deleting objects under it when write delegation is returned.
- CVE-2026-42809Critical
Apache Polaris issues broad temporary (vended) storage credentials during staged table creation before the effective table location has been validated or durably reserved. An attacker can supply a custom location (or write.data.path/write.metadata.path), making the credential scope attacker-directed.
- CVE-2026-97395High
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, Polaris may use these settings to construct its server-side FileIO client, potentially redirecting storage traffic to a host chosen by the table writer and exposing authentication material.
- CVE-2026-64640Medium
Apache Polaris did not consistently validate storage locations supplied during table and view registration. An authenticated principal with registration permissions could cause Polaris to use the catalog's storage credentials to read a caller-selected Iceberg metadata file before verifying it was within allowed locations, potentially disclosing limited information. Polaris could also accept registration metadata with references to external locations, but this did not cause reads.
Original NVD description (English source)
In plain terms, Apache Polaris is supposed to issue short-lived GCS credentials that only work for one table's files, but a crafted namespace or table name can cause those credentials to work across the configured bucket instead. Apache Polaris builds Google Cloud Storage downscoped credentials by creating a Credential Access Boundary (CAB) with CEL conditions that are intended to restrict access to the requested table's storage path. The relevant CEL string is built from the bucket name and the table path. That table path is derived from namespace and table identifiers. In current code, that path appears to be inserted into the CEL expression without escaping. As a result, a namespace or table identifier containing a single quote and other URI-safe CEL fragments can break out of the intended quoted string and change the meaning of the CEL condition. In private testing against Polaris 1.4.0 on real Google Cloud Storage, it was confirmed that Polaris accepted a crafted identifier and returned delegated GCS credentials whose CEL path restriction had effectively collapsed. Those delegated credentials could then: - list another table's object prefix; - read another table's metadata control file (Iceberg metadata JSON); - create and delete an object under another table's object prefix; - and also list, read, create, and delete objects under an unrelated external prefix in the same bucket that was not part of any table path. That last point is important. The issue is not limited to "another table". In the confirmed setup, once Apache Polaris returned credentials for the crafted table, the path restriction inside the configured bucket was effectively gone. The practical effect is that temporary credentials for one crafted table can be broader than the table Polaris was asked to authorize, and can become effectively bucket-wide within the configured bucket. The current GCS testing used a Polaris principal with broad catalog privileges for setup. A separate least-privilege Polaris RBAC variant has not yet been tested on GCS. However, the storage-credential broadening behavior itself has been confirmed on GCS.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS