{"id":"CVE-2026-40937","aliases":["GHSA-pfcq-4gjr-6gjm"],"url":"https://o3.security/vulnerability/CVE-2026-40937","summary":"RustFS missing admin authorization on notification target endpoints, which allows unauthenticated configuration of event webhooks","details":"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.","published":"2026-04-22T20:15:57.266Z","modified":"2026-08-12T03:51:12.017164719Z","cvss":{"score":8.3,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:L"},"epss":{"score":0.00293,"percentile":0.21638,"asOf":"2026-08-12"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"crates.io","name":"rustfs","fixedVersion":null}],"fix":null,"references":[{"type":"WEB","url":"https://github.com/rustfs/rustfs/releases/tag/1.0.0-alpha.94"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/40xxx/CVE-2026-40937.json"},{"type":"ADVISORY","url":"https://github.com/rustfs/rustfs/security/advisories/GHSA-pfcq-4gjr-6gjm"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-40937"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:12.017164719Z"}}