{"cve":"CVE-2026-27607","nvd":{"published":"2026-02-25T03:16:04.787","modified":"2026-06-17T10:27:23.027","status":"Analyzed","description":"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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H","score":9.1},"cwes":["CWE-863","CWE-20"],"references":["https://github.com/rustfs/rustfs/security/advisories/GHSA-w5fh-f8xh-5x3p"],"products":["rustfs:rustfs"],"source":"nvd","synced_at":"2026-10-19T22:24:17.937441719+00:00"},"epss":{"cve":"CVE-2026-27607","score":0.00369,"percentile":0.30758,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-w5fh-f8xh-5x3p","url":"https://osv.dev/vulnerability/GHSA-w5fh-f8xh-5x3p","summary":"RustFS: Missing Post Policy Validation leads to Arbitrary Object Write","modified":"2026-02-25T22:47:39.717003Z","packages":[{"ecosystem":"crates.io","name":"rustfs","purl":"pkg:cargo/rustfs","ranges":[">=1.0.0-alpha.56 <1.0.0-alpha.83"],"fixed":["1.0.0-alpha.83"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}