CVE-2026-39360
RustFS has an authorization bypass in multipart UploadPartCopy enables cross-bucket object exfiltration
- State
- Published
- Severity
- 5.3 Medium
- Published
- Apr 7, 2026
- Updated
- Apr 7, 2026
- Reserved
- Apr 6, 2026
Description
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.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 4.0 | 5.3 Medium | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N | GitHub_M |
Weaknesses
- CWE-862 Missing Authorization
Affected Products
| Product | Versions |
|---|---|
rustfsrustfs |
|
References
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