CVE-2026-71191

unknown

Published 2026-08-05 · Modified 2026-08-05

CVSS v3

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CVSS v4 NEW

6.0

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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

VIR risk

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Description

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.

Predictions

Exploit likelihood

20%

Patch ETA

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Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No mitigations published for this CVE yet.

The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.

Propose a mitigation on Community Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here with source_tier=community-verified.

References

CWEs

CWE-863

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.