PT-2026-34559 · Rustfs · Rustfs

Published 2026-04-22 · Updated 2026-04-22 · CVE-2026-40937

Mitre

CVSS v3.1

8.3

High

AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:L

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.

Fix

Missing Authorization

Weakness Enumeration

CWE-862

Related Identifiers

CVE-2026-40937

Affected Products

Rustfs

References · 3

• https://nvd.nist.gov/vuln/detail/CVE-2026-40937 · Security Note
• https://github.com/rustfs/rustfs/security/advisories/GHSA-pfcq-4gjr-6gjm · Note
• https://github.com/rustfs/rustfs/releases/tag/1.0.0-alpha.94 · Note