CVE-2026-40937

Published Apr 22, 2026

Last updated 7 days ago

CVSS high 8.3

Overview

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.
Source
security-advisories@github.com
NVD status
Analyzed
Products
rustfs

Risk scores

CVSS 3.1

Type
Secondary
Base score
8.3
Impact score
5.5
Exploitability score
2.8
Vector string
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:L
Severity
HIGH

Weaknesses

security-advisories@github.com
CWE-862

Social media

Hype score
Not currently trending

Configurations

Related CVEs

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  2. RustFS is a distributed object storage system built in Rust. Prior to version 1.0.0-alpha.83, a Stored Cross-Site Scripting (XSS) vulnerability in the RustFS Console allows an attacker to execute arbitrary JavaScript in the context of the management console. By bypassing the PDF preview logic, an attacker can steal administrator credentials from `localStorage`, leading to full account takeover and system compromise. Version 1.0.0-alpha.83 fixes the issue.•CVE-2026-27822
  3. RustFS is a distributed object storage system built in Rust. In versions 1.0.0-alpha.56 through 1.0.0-alpha.82, RustFS does not validate policy conditions in presigned POST uploads (PostObject), allowing attackers to bypass content-length-range, starts-with, and Content-Type constraints. This enables unauthorized file uploads exceeding size limits, uploads to arbitrary object keys, and content-type spoofing, potentially leading to storage exhaustion, unauthorized data access, and security bypasses. Version 1.0.0-alpha.83 fixes the issue.•CVE-2026-27607
  4. RustFS is a distributed object storage system built in Rust. From versions alpha.13 to alpha.81, RustFS logs sensitive credential material (access key, secret key, session token) to application logs at INFO level. This results in credentials being recorded in plaintext in log output, which may be accessible to internal or external log consumers and could lead to compromise of sensitive credentials. This issue has been patched in version alpha.82.•CVE-2026-24762
  5. RustFS is a distributed object storage system built in Rust. Prior to version alpha.78, IP-based access control can be bypassed: get_condition_values trusts client-supplied X-Forwarded-For/X-Real-Ip without verifying a trusted proxy, so any reachable client can spoof aws:SourceIp and satisfy IP-allowlist policies. This issue has been patched in version alpha.78.•CVE-2026-21862

References

Sources include official advisories and independent security research.