In OpenStack Swift through 2.38.0, the S3API middleware does not sanitize Swift-native control headers (X-Copy-From, X-Copy-From-Account) from S3 API requests when s3_acl=true. An
attacker can inject these headers into a signed PUT request targeting their own bucket, causing Swift to perform a server-side copy from another tenant's private object. The source object authorization is bypassed because the S3API middleware has already authorized the request against the destination. The attacker can read any object whose project_id, container name, and object name are known, regardless of the source object's ACLs or ownership. This requires the non-default s3_acl=true configuration.

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History

Wed, 05 Aug 2026 06:45:00 +0000

Type Values Removed Values Added
Title S3API Middleware Allows Unauthorized Server‑Side Copy in OpenStack Swift

Wed, 05 Aug 2026 05:30:00 +0000

Type Values Removed Values Added
Description In OpenStack Swift through 2.38.0, the S3API middleware does not sanitize Swift-native control headers (X-Copy-From, X-Copy-From-Account) from S3 API requests when s3_acl=true. An attacker can inject these headers into a signed PUT request targeting their own bucket, causing Swift to perform a server-side copy from another tenant's private object. The source object authorization is bypassed because the S3API middleware has already authorized the request against the destination. The attacker can read any object whose project_id, container name, and object name are known, regardless of the source object's ACLs or ownership. This requires the non-default s3_acl=true configuration.
First Time appeared Openstack
Openstack swift
Weaknesses CWE-863
CPEs cpe:2.3:a:openstack:swift:*:*:*:*:*:*:*:*
Vendors & Products Openstack
Openstack swift
References
Metrics cvssV4_0

{'score': 6, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N'}


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cve-icon MITRE

Status: PUBLISHED

Assigner: mitre

Published:

Updated: 2026-08-05T05:05:33.267Z

Reserved: 2026-08-05T05:05:32.904Z

Link: CVE-2026-71192

cve-icon Vulnrichment

No data.

cve-icon NVD

No data.

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-08-05T09:00:05Z

Weaknesses