{"cve":"CVE-2026-6321","nvd":{"published":"2026-05-04T20:16:20.950","modified":"2026-09-10T13:20:28.160","status":"Modified","description":"fast-uri decoded percent-encoded path separators and dot segments before applying dot-segment removal in its normalize() and equal() functions. Encoded path data was treated like real slashes and parent-directory references, so distinct URIs could collapse onto the same normalized path. Applications that normalize or compare attacker-controlled URLs to enforce path-based policy can be bypassed, with a path that appears confined under an allowed prefix normalizing to a different location. Versions <= 3.1.0 are affected. Update to 3.1.1 or later.","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:N","score":7.5},"cwes":["CWE-22"],"references":["https://cna.openjsf.org/security-advisories.html","https://github.com/fastify/fast-uri/security/advisories/GHSA-q3j6-qgpj-74h6","https://access.redhat.com/errata/RHSA-2026:19238","https://access.redhat.com/errata/RHSA-2026:20338","https://access.redhat.com/errata/RHSA-2026:21338"],"products":["openjsf:fast-uri"],"source":"nvd","synced_at":"2026-10-19T22:33:09.003606135+00:00"},"epss":{"cve":"CVE-2026-6321","score":0.00634,"percentile":0.50399,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-q3j6-qgpj-74h6","url":"https://osv.dev/vulnerability/GHSA-q3j6-qgpj-74h6","summary":"fast-uri vulnerable to path traversal via percent-encoded dot segments","modified":"2026-09-10T03:51:06.746866846Z","packages":[{"ecosystem":"npm","name":"fast-uri","purl":"pkg:npm/fast-uri","ranges":[">=3.0.0 <3.1.1"],"fixed":["3.1.1"]},{"ecosystem":"npm","name":"fast-uri","purl":"pkg:npm/fast-uri","ranges":["<2.4.1"],"fixed":["2.4.1"]}]}],"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."]}