CVE-2026-39360 — RustFS has an authorization bypass in multipart UploadPartCopy enables cross-bucket object exfiltration
RustFS is a distributed object storage system built in Rust. Prior to alpha.90, RustFS contains a missing authorization check in the multipart copy path (UploadPartCopy). A low-…
Published: 2026-04-07 · CVSS: 5.3 · CVSS 4.0
RustFS is a distributed object storage system built in Rust. Prior to alpha.90, RustFS contains a missing authorization check in the multipart copy path (UploadPartCopy). A low-privileged user who cannot read objects from a victim bucket can still exfiltrate victim objects by copying them into an attacker-controlled multipart upload and completing the upload. This breaks tenant isolation in multi-user / multi-tenant deployments. This vulnerability is fixed in alpha.90.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7