CVE-2026-71191
In OpenStack Swift through 2.38.0, S3API middleware does not enforce that semantic x-amz-* headers are covered by the SigV4 signature on presigned URL requests. An attacker who obtains a presigned PUT URL can inject an unsigned X-Amz-Copy-Source header, causing Swift to perform a server-side copy from an arbitrary source object using the signer's authorization context. The attacker can read any object the signer has access to, provided the target project_id, container name, and object name are known. This affects all deployments using the default s3_acl=false configuration.
- Score
- CVSS 4.0 6.0 Medium
- Status
- Awaiting Analysis - cve@mitre.org
- Published
- 2026-08-05
- Last modified
- 2026-10-24
- Weaknesses
- CWE-863
Affected products
References
- https://launchpad.net/bugs/2158733
- https://openwall.com/lists/oss-security/2026/07/28/26
- https://security.openstack.org/ossa/OSSA-2026-030.html
