{"cve":"CVE-2020-36321","nvd":{"published":"2021-04-23T16:15:08.403","modified":"2026-06-17T03:15:18.163","status":"Modified","description":"Improper URL validation in development mode handler in com.vaadin:flow-server versions 2.0.0 through 2.4.1 (Vaadin 14.0.0 through 14.4.2), and 3.0 prior to 5.0 (Vaadin 15 prior to 18) allows attacker to request arbitrary files stored outside of intended frontend resources folder.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","score":7.5},"cwes":["CWE-22"],"references":["https://github.com/vaadin/flow/pull/9392","https://vaadin.com/security/cve-2020-36321","https://github.com/vaadin/flow/pull/9392","https://vaadin.com/security/cve-2020-36321"],"products":["vaadin:flow","vaadin:vaadin"],"source":"nvd","synced_at":"2026-10-19T21:17:01.373894544+00:00"},"epss":{"cve":"CVE-2020-36321","score":0.01211,"percentile":0.68462,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-49r2-73m6-pp8f","url":"https://osv.dev/vulnerability/GHSA-49r2-73m6-pp8f","summary":"Directory traversal in development mode handler in Vaadin 14 and 15-17","modified":"2023-11-08T04:03:43.499388Z","packages":[{"ecosystem":"Maven","name":"com.vaadin:flow-server","purl":"pkg:maven/com.vaadin/flow-server","ranges":[">=3.0.0 <5.0.0"],"fixed":["5.0.0"]},{"ecosystem":"Maven","name":"com.vaadin:flow-server","purl":"pkg:maven/com.vaadin/flow-server","ranges":[">=2.0.0 <2.4.2"],"fixed":["2.4.2"]}]}],"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."]}