RustFS up to 1.0.0-alpha.93 API Endpoint event.rs check_permissions authorization

CVSS Meta Temp Score
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CTI Interest Score
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7.1$0-$5k0.00

Summaryinfo

A vulnerability was found in RustFS up to 1.0.0-alpha.93. It has been declared as critical. Impacted is the function check_permissions of the file rustfs/src/admin/handlers/event.rs of the component API Endpoint. Such manipulation leads to authorization. This vulnerability is listed as CVE-2026-40937. The attack may be performed from remote. There is no available exploit. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in RustFS up to 1.0.0-alpha.93 and classified as critical. Affected by this issue is the function check_permissions of the file rustfs/src/admin/handlers/event.rs of the component API Endpoint. The manipulation with an unknown input leads to a authorization vulnerability. Using CWE to declare the problem leads to CWE-862. The product does not perform an authorization check when an actor attempts to access a resource or perform an action. Impacted is confidentiality, integrity, and availability. CVE summarizes:

RustFS is a distributed object storage system built in Rust. Prior to 1.0.0-alpha.94, all four notification target admin API endpoints in `rustfs/src/admin/handlers/event.rs` use a `check_permissions` helper that validates authentication only (access key + session token), without performing any admin-action authorization via `validate_admin_request`. Every other admin handler in the codebase correctly calls `validate_admin_request` with a specific `AdminAction`. This is the only admin handler file that skips authorization. A non-admin user can overwrite a shared admin-defined notification target by name, causing subsequent bucket events to be delivered to an attacker-controlled endpoint. This enables cross-user event interception and audit evasion. 1.0.0-alpha.94 contains a patch.

The advisory is available at github.com. This vulnerability is handled as CVE-2026-40937 since 04/15/2026. The exploitation is known to be easy. The attack may be launched remotely. Technical details are known, but there is no available exploit.

Upgrading to version 1.0.0-alpha.94 eliminates this vulnerability. The upgrade is hosted for download at github.com.

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Productinfo

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.3
VulDB Meta Temp Score: 7.1

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 8.3
CNA Vector (GitHub_M): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Authorization
CWE: CWE-862 / CWE-863 / CWE-285
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: RustFS 1.0.0-alpha.94

Timelineinfo

04/15/2026 CVE reserved
04/23/2026 +8 days Advisory disclosed
04/23/2026 +0 days VulDB entry created
04/23/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: GHSA-pfcq-4gjr-6gjm
Status: Confirmed

CVE: CVE-2026-40937 (🔒)
GCVE (CVE): GCVE-0-2026-40937
GCVE (VulDB): GCVE-100-359078

Entryinfo

Created: 04/23/2026 06:50
Changes: 04/23/2026 06:50 (66)
Complete: 🔍
Cache ID: 216::103

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