{"id":"CVE-2026-54330","title":"Ceph is an open-source distributed storage platform providing object, block, and file storage","summary":"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…","severity":"high","cvss":8.1,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N","cwe":["CWE-347"],"published":"2026-08-28","updated":"2026-09-08","sourceUpdated":"2026-09-08T21:11:56.250","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-54330","references":[{"url":"https://github.com/ceph/ceph/commit/5837aa8e60471128dbb672b0ff6f1b1feebe08a7","label":"security-advisories@github.com"},{"url":"https://github.com/ceph/ceph/commit/5978c866d4a0812fbb024745c4f1e79aaecd6c6a","label":"security-advisories@github.com"},{"url":"https://github.com/ceph/ceph/security/advisories/GHSA-rmjq-ffrm-j6vj","label":"security-advisories@github.com"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-54330.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-54330"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2519428"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-54330"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-54330"},{"url":"https://access.redhat.com/errata/RHSA-2026:79101"},{"url":"https://access.redhat.com/errata/RHSA-2026:79243"}],"tags":["nvd","csaf","vex","red-hat"],"epss":0.00367,"epssPercentile":0.30395,"ingestedAt":"2026-09-08T22:12:30.941Z","vendor":"Red Hat","product":"Red Hat Ceph Storage 8.1 Tools","affected":["ceph_storage 4","ceph_storage 5","ceph_storage 6","ceph_storage 7","ceph_storage 9","ceph_storage_8_1_tools","ceph_storage 8.1"],"patched":["ceph_storage_8_1_tools","ceph_storage 8.1"],"scores":{"nvd":8.1,"vendor":8.2},"slug":"CVE-2026-54330","body":"## Overview\n\nCeph 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 presigned URL to attach arbitrary unsigned x-amz-* headers that RGW will honor. AWS S3 requires every x-amz-* header on a SigV4 request to be signed and rejects requests bearing additional unsigned headers, but RGW validates only the headers listed in X-Amz-SignedHeaders and ignores any extra ones, so they take effect without being covered by the signature. By adding such headers to a presigned PUT URL, an attacker can grant themselves more capabilities than the URL's signer intended and escalate their privileges. This issue is fixed in versions 20.2.4 and 19.2.6.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Vendor advisories\n\n- **RHSA-2026:79101** · Red Hat · fixed in: Red Hat Ceph Storage 8.1 Tools · released 2026-10-08 · [advisory](https://access.redhat.com/errata/RHSA-2026:79101)\n- **RHSA-2026:79243** · Red Hat · fixed in: Red Hat Ceph Storage 8.1 · released 2026-10-08 · [advisory](https://access.redhat.com/errata/RHSA-2026:79243)\n- **Red Hat VEX** · Important · affected: Red Hat Ceph Storage 4, Red Hat Ceph Storage 5, Red Hat Ceph Storage 6, Red Hat Ceph Storage 7, Red Hat Ceph Storage 9 · no fix planned: Red Hat Ceph Storage 4, Red Hat Ceph Storage 5, Red Hat Ceph Storage 6, Red Hat Ceph Storage 7, … · updated 2026-10-09 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-54330.json)","depth":"twilight","depthScore":45,"depthScoreParts":{"impact":44.6,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}