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

Overview

Severity

High (CVSS 8.1)

CVSS Vector

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

Exploit Status

Not Exploited

Patch Tuesday

2026-Aug

Released

2026-09-02

EPSS Score

0.18% (percentile: 7.8%)

Affected Products (1)

Other

• 20730-17084

Revision History

• 2026-09-02: Information published.