{"api_version":"1","generated_at":"2026-09-25T09:08:32+00:00","cve":"CVE-2026-97731","urls":{"html":"https://cve.report/CVE-2026-97731","api":"https://cve.report/api/cve/CVE-2026-97731.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-97731","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-97731"},"summary":{"title":"CVE-2026-97731","description":"MinIO through 7aac2a2 does not verify that every x-amz-* header present on a request also appears in the client-supplied X-Amz-SignedHeaders list. extractSignedHeaders() in cmd/signature-v4-utils.go iterates only the claimed list and never enumerates the headers that actually arrived, and thus a header that arrives unsigned is neither hashed into the canonical request nor rejected. Because cmd/api-router.go dispatches CopyObject on the presence of x-amz-copy-source alone, the holder of a presigned PUT URL scoped to a single object can add that header to the unmodified URL and cause a server-side copy, executed as the signer, of any object the signing key can read. A grant to write one object becomes a read of every bucket that key can reach. Amazon S3 rejects the equivalent request with HTTP 403 AccessDenied. 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Because cmd/api-router.go dispatches CopyObject on the presence of x-amz-copy-source alone, the holder of a presigned PUT URL scoped to a single object can add that header to the unmodified URL and cause a server-side copy, executed as the signer, of any object the signing key can read. A grant to write one object becomes a read of every bucket that key can reach. Amazon S3 rejects the equivalent request with HTTP 403 AccessDenied. 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Because cmd/api-router.go dispatches CopyObject on the presence of x-amz-copy-source alone, the holder of a presigned PUT URL scoped to a single object can add that header to the unmodified URL and cause a server-side copy, executed as the signer, of any object the signing key can read. A grant to write one object becomes a read of every bucket that key can reach. Amazon S3 rejects the equivalent request with HTTP 403 AccessDenied. The minio/minio GitHub repository was archived in April 2026; pgsty/silo before 1233254 is also affected.","Type":"Description","Title":"CVE-2026-97731"}]}}}