{"id":"CVE-2026-6321","aliases":["GHSA-q3j6-qgpj-74h6"],"url":"https://o3.security/vulnerability/CVE-2026-6321","summary":"fast-uri vulnerable to path traversal via percent-encoded dot segments","details":"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.","published":"2026-05-04T19:31:57.253Z","modified":"2026-08-07T11:31:18.831233443Z","cvss":{"score":7.5,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"npm","name":"fast-uri","fixedVersion":"3.1.1"}],"fix":null,"references":[{"type":"WEB","url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-6321.json"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:19238"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:20338"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:21338"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:24473"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:24766"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:24866"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:24977"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:25089"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:25123"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:26214"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:26234"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:26416"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:26420"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:34342"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:37385"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:42078"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2026:42079"},{"type":"ADVISORY","url":"https://access.redhat.com/security/cve/CVE-2026-6321"},{"type":"ADVISORY","url":"https://cna.openjsf.org/security-advisories.html"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/6xxx/CVE-2026-6321.json"},{"type":"ADVISORY","url":"https://github.com/fastify/fast-uri/security/advisories/GHSA-q3j6-qgpj-74h6"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-6321"},{"type":"REPORT","url":"https://bugzilla.redhat.com/show_bug.cgi?id=2466582"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-07T11:31:18.831233443Z"}}