SeaweedFS: Improper authorization in the S3Tables / Iceberg REST management API lets a low-privileged S3 user enumerate administrator-owned table buckets

### Summary SeaweedFS routes requests signed with SigV4 service `s3tables` to the S3Tables management API. Authorization on that path collapsed account-less S3 identities into the shared `admin` account and failed open, so a user holding only ordinary S3 `Read` credentials , and no S3Tables-specific permission , could invoke S3Tables management operations such as `GET /buckets` and enumerate administrator-owned table bucket inventory (names and ARNs). The same handler backs the Iceberg REST catalog, which was affected by the same flaw. ### Impact An authenticated low-privileged S3 user can cross the boundary between ordinary S3 object access and S3Tables management. Confirmed impact is disclosure of administrator-owned table bucket inventory (bucket names and ARNs); in shared or multi-tenant deployments this can reveal tenant naming and operational structure. ### Affected versions SeaweedFS `>= 4.08, < 4.34` (the S3Tables management API was introduced in 4.08). ### Patched versions Fixed in **4.34** (#9961). Administrator status is now decided by the `ACTION_ADMIN` capability rather than by a collapsed `admin` account id, S3Tables authorization no longer defaults to allow, and the tautological ListTableBuckets gate was removed. Related hardening of the same root cause landed in #9962, #9963, and #9971. ### Workaround No configuration workaround , upgrade to 4.34 or later. ### Credit Reported by **TA-MU-TA**.

CVSS 3.1

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N

Severity from

GitHub (reviewed advisory)

Weakness

CWE-863

Also known as

BIT-seaweedfs-2026-55873, CVE-2026-55873, GO-2026-6329

• github.com/seaweedfs/seaweedfs/security/advisories/GHSA-hgpf-8634-g44c
• nvd.nist.gov/vuln/detail/CVE-2026-55873
• github.com/seaweedfs/seaweedfs/pull/9961
• github.com/seaweedfs/seaweedfs/commit/b13463880c1fa62e255c058a9228b63cc95b4b36
• github.com/seaweedfs/seaweedfs
• github.com/seaweedfs/seaweedfs/releases/tag/4.34