PT-2026-30978 · Rustfs · Rustfs

Thesmartshadow · Published 2026-04-07 · Updated 2026-04-08 · CVE-2026-39360

Positive Technologies (AI Summary)

CVSS v4.0

5.3

Medium

Base vector

AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N

Name of the Vulnerable Software and Affected Versions RustFS versions prior to alpha.90

Description RustFS, a distributed object storage system built in Rust, had a missing authorization check in the multipart copy path (UploadPartCopy) before version alpha.90. This allowed a low-privileged user, lacking read access to objects in a victim bucket, to exfiltrate those objects by copying them into a multipart upload they control and then completing the upload. This compromised tenant isolation in multi-user or multi-tenant deployments.

Recommendations Update to version alpha.90 or later.

Fix

Missing Authorization

Weakness Enumeration

CWE-862

Related Identifiers

CVE-2026-39360

GHSA-MX42-J6WV-PX98

Affected Products

Rustfs

References · 6

• https://github.com/rustfs/rustfs/security/advisories/GHSA-mx42-j6wv-px98 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-39360 · Security Note
• https://osv.dev/vulnerability/GHSA-mx42-j6wv-px98 · Vendor Advisory
• https://github.com/rustfs/rustfs · Note
• https://reddit.com/r/VulnMatter/comments/1sft88v/resumen_diario_de_vulnerabilidades_08042026 · Reddit Post
• https://twitter.com/CVEnew/status/2041603150864417246 · Twitter Post