CVE-2026-40937

RustFS missing admin authorization on notification target endpoints, which allows unauthenticated configuration of event webhooks

HIGH
8.3
CVSS Score
Published: April 22, 2026 at 08:15 PM UTC
Updated: June 17, 2026 at 10:45 AM UTC
1 product affected across 1 vendorRustfs

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Severity
HIGH8.3
Exploit prediction
EPSS 0.3%
SSVC
No known exploit

Description

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.

Affected

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (2)

x_refsource_CONFIRMMitigationVendor Advisory
Source: cverecord
https://github.com/rustfs/rustfs/security/advisories/GHSA-pfcq-4gjr-6gjm
x_refsource_MISCProductRelease Notes
Source: cverecord
https://github.com/rustfs/rustfs/releases/tag/1.0.0-alpha.94

SSVC — Action Prioritization

SSVCNo known exploitNot automatableTotal impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

8.3HIGHGitHub_M
Attack Vector
NETWORK
Complexity
LOW
Privileges
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
LOW
Vector?

Quick Info

StatusANALYZED
CWE
CWE-862

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