CVE-2026-45042CWE-863

RustFS: UploadPartCopy Does Not Enforce Destination Bucket Policy on Copy Source

High · published May 28, 2026

CVSS v4.0
7.1
EPSS
0%
Percentile
27.5
In the wild
Unconfirmed
What it is

RustFS is a distributed object storage system built in Rust. Prior to 1.0.0-beta.2, improper authorization in the UploadPartCopy operation allows copying objects across buckets without enforcing destination bucket restrictions on allowed copy sources. The implementation validates GetObject permission on the source bucket and PutObject on the destination bucket independently, but does not enforce any policy constraints on whether the destination bucket permits the specified copy source. This enables unauthorized cross-bucket data movement. This vulnerability is fixed in 1.0.0-beta.2.

The record
Technical detail
CVSS v4.0
7.1 · HIGH
Vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
EPSS
0.00351 · 27.5th percentile
Weakness
CWE-863 · Incorrect Authorization
Published
2026-05-28T18:32Z
EPSS history
Timeline
  • 28 MAY 18:32Z
    RustFS: UploadPartCopy Does Not Enforce Destination Bucket Policy on Copy Source
    cvelistv5