CVE-2026-54330

high Red Hat
CVSS v3 Base Score
8.2
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:N
Attack Characteristics
Attack Vector
Network
Attack Complexity
High
Privileges Required
Low
User Interaction
None
Confidentiality
High
Integrity
High
Availability
None
Published: August 19, 2026 (18 days ago)
Last Modified: August 19, 2026
Vendor: Red Hat
Source: REDHAT

Description

A flaw was found in Ceph RGW's SigV4 signature verification handler. When processing S3 requests, RGW verifies only the headers explicitly listed in the X-Amz-SignedHeaders field but does not reject requests that carry additional unsigned x-amz-* headers. This diverges from the AWS S3 specification, which requires all x-amz-* headers to be signed. As a result, anyone holding a presigned PUT URL can attach arbitrary unsigned x-amz-* headers that RGW will honor, effectively escalating their privileges beyond what the original URL signer authorized. This can lead to unauthorized access to and modification of S3 objects.

CWE

CWE-347

Affected Products

Red Hat Ceph Storage 4Red Hat Ceph Storage 5Red Hat Ceph Storage 6Red Hat Ceph Storage 7Red Hat Ceph Storage 8Red Hat Ceph Storage 9

References

🔗 bugzilla.redhat.com 🔗 www.cve.org 🔗 nvd.nist.gov