RustFS up to alpha.89 Multipart Upload authorization

Summaryinfo

A vulnerability was found in RustFS up to alpha.89 and classified as problematic. The impacted element is an unknown function of the component Multipart Upload Handler. Executing a manipulation can lead to authorization. This vulnerability is tracked as CVE-2026-39360. The attack can be launched remotely. No exploit exists. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in RustFS up to alpha.89. It has been declared as problematic. This vulnerability affects an unknown code of the component Multipart Upload Handler. The manipulation with an unknown input leads to a authorization vulnerability. The CWE definition for the vulnerability is CWE-862. The product does not perform an authorization check when an actor attempts to access a resource or perform an action. As an impact it is known to affect confidentiality. CVE summarizes:

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.

The advisory is shared for download at github.com. This vulnerability was named CVE-2026-39360 since 04/06/2026. The exploitation appears to be easy. The attack can be initiated remotely. There are neither technical details nor an exploit publicly available.

Upgrading to version alpha.90 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-19867). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Name

• RustFS

Version

• alpha.0
• alpha.1
• alpha.2
• alpha.3
• alpha.4
• alpha.5
• alpha.6
• alpha.7
• alpha.8
• alpha.9
• alpha.10
• alpha.11
• alpha.12
• alpha.13
• alpha.14
• alpha.15
• alpha.16
• alpha.17
• alpha.18
• alpha.19
• alpha.20
• alpha.21
• alpha.22
• alpha.23
• alpha.24
• alpha.25
• alpha.26
• alpha.27
• alpha.28
• alpha.29
• alpha.30
• alpha.31
• alpha.32
• alpha.33
• alpha.34
• alpha.35
• alpha.36
• alpha.37
• alpha.38
• alpha.39
• alpha.40
• alpha.41
• alpha.42
• alpha.43
• alpha.44
• alpha.45
• alpha.46
• alpha.47
• alpha.48
• alpha.49
• alpha.50
• alpha.51
• alpha.52
• alpha.53
• alpha.54
• alpha.55
• alpha.56
• alpha.57
• alpha.58
• alpha.59
• alpha.60
• alpha.61
• alpha.62
• alpha.63
• alpha.64
• alpha.65
• alpha.66
• alpha.67
• alpha.68
• alpha.69
• alpha.70
• alpha.71
• alpha.72
• alpha.73
• alpha.74
• alpha.75
• alpha.76
• alpha.77
• alpha.78
• alpha.79
• alpha.80
• alpha.81
• alpha.82
• alpha.83
• alpha.84
• alpha.85
• alpha.86
• alpha.87
• alpha.88
• alpha.89

Website

• Product: https://github.com/rustfs/rustfs/

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

VulDB is the best source for vulnerability data and more expert information about this specific topic.

Discussion