CVE-2026-40937

What it is

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.

At a glance

Exploitability

Can be exploited over the network with a low-privilege account. High risk of data exposure, data tampering.

Exploit odds

0.3% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2026-04-22 21:17 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-06-17 10:45 UTC Last updatedMost recent change to the record

Details

Published

2026-04-22 21:17 UTC

Last modified

2026-06-17 10:45 UTC

Exploit probability

0.3% · EPSS, next 30 days

Weakness

CWE-862 · Missing authorization

Record status

Analyzed

Affected

• Rustfs 1.0.0

Attack profile CVSS 3.1 · 8.3

Attack vector

Network

Complexity

Low

Privileges needed

Low

User interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

Low