CVE-2026-54330 Ceph RGW SigV4 handler accepts unsigned x-amz-* headers on presigned requests, allowing privilege escalation

Ceph is an open-source distributed storage platform providing object, block, and file storage. In versions prior to 20.2.4 and 19.2.6, the Ceph Object Gateway RGW SigV4 handler does not reject requests that carry x-amz- headers absent from the signed header set, allowing anyone holding a presigne...