{ "affected": [ { "package": { "ecosystem": "npm", "name": "fast-uri" }, "ranges": [ { "events": [ { "introduced": "4.0.0" }, { "fixed": "4.0.1" } ], "type": "ECOSYSTEM" } ] }, { "package": { "ecosystem": "npm", "name": "fast-uri" }, "ranges": [ { "events": [ { "introduced": "3.0.0" }, { "fixed": "3.1.3" } ], "type": "ECOSYSTEM" } ] }, { "package": { "ecosystem": "npm", "name": "fast-uri" }, "ranges": [ { "events": [ { "introduced": "2.3.1" }, { "fixed": "2.4.2" } ], "type": "ECOSYSTEM" } ] } ], "aliases": [ "CVE-2026-13676" ], "database_specific": { "cwe_ids": [ "CWE-436", "CWE-551" ], "github_reviewed": true, "github_reviewed_at": "2026-07-21T19:03:11Z", "nvd_published_at": "2026-06-29T14:16:47Z", "severity": "HIGH" }, "details": "### Impact\n\n`fast-uri` versions `>= 2.3.1, <= 4.0.0` fail to canonicalize Unicode/IDN hostnames for HTTP-family URLs. The IDN conversion path calls `URL.domainToASCII(...)` on the global WHATWG `URL` constructor, where that helper does not exist. The resulting `TypeError` is silently routed into `parsed.error`, but `parse()`, `normalize()`, and `equal()` all return with the host left in its original Unicode form.\n\nFor example, `http://127。0。0。1/` is treated by `fast-uri` as host `127。0。0。1`, while Node's WHATWG URL parser and `fetch()` canonicalize the same input to `127.0.0.1`.\n\nApplications that use `fast-uri` to enforce host-based policy (denylists, loopback filtering, redirect validation, outbound proxy routing) before passing the same URL into Node's URL or `fetch()` consumers see a policy/use desync and can be steered to an unintended destination.\n\n### Patches\n\nUpgrade to `fast-uri` v4.0.1, v3.1.3, or v2.4.2\n\n### Workarounds\n\nNone. Upgrade to the patched version.", "id": "GHSA-4c8g-83qw-93j6", "modified": "2026-09-11T15:32:25Z", "published": "2026-07-21T19:03:11Z", "references": [ { "type": "WEB", "url": "https://github.com/fastify/fast-uri/security/advisories/GHSA-4c8g-83qw-93j6" }, { "type": "ADVISORY", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-13676" }, { "type": "WEB", "url": "https://github.com/fastify/fast-uri/pull/188" }, { "type": "WEB", "url": "https://github.com/fastify/fast-uri/commit/2a6d357a18a68e6d812824379fd3388a1ae50d05" }, { "type": "WEB", "url": "https://github.com/fastify/fast-uri/commit/21ea1f9d70495c931f55dff893a8fa38f4f2e6bd" }, { "type": "WEB", "url": "https://github.com/fastify/fast-uri/commit/01db48010f594b98f7b323be18b393791c66ed1d" }, { "type": "WEB", "url": "https://access.redhat.com/errata/RHSA-2026:63371" }, { "type": "WEB", "url": "https://access.redhat.com/errata/RHSA-2026:61314" }, { "type": "WEB", "url": "https://access.redhat.com/errata/RHSA-2026:60520" }, { "type": "WEB", "url": "https://access.redhat.com/errata/RHSA-2026:60386" }, { "type": "WEB", "url": "https://access.redhat.com/errata/RHSA-2026:59593" }, { "type": "WEB", "url": "https://access.redhat.com/errata/RHSA-2026:57590" }, { "type": "WEB", "url": "https://access.redhat.com/errata/RHSA-2026:57194" }, { "type": "WEB", "url": "https://access.redhat.com/errata/RHSA-2026:57191" }, { "type": "WEB", "url": "https://access.redhat.com/errata/RHSA-2026:57013" }, { "type": "WEB", "url": "https://access.redhat.com/errata/RHSA-2026:56431" }, { "type": "WEB", "url": "https://access.redhat.com/errata/RHSA-2026:56366" }, { "type": "WEB", "url": "https://access.redhat.com/errata/RHSA-2026:66488" }, { "type": "WEB", "url": "https://access.redhat.com/errata/RHSA-2026:66545" }, { "type": "WEB", "url": "https://access.redhat.com/security/cve/CVE-2026-13676" }, { "type": "WEB", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2494197" }, { "type": "WEB", "url": "https://cna.openjsf.org/security-advisories.html" }, { "type": "PACKAGE", "url": "https://github.com/fastify/fast-uri" }, { "type": "WEB", "url": "https://github.com/fastify/fast-uri/releases/tag/v2.4.2" }, { "type": "WEB", "url": "https://github.com/fastify/fast-uri/releases/tag/v3.1.3" }, { "type": "WEB", "url": "https://github.com/fastify/fast-uri/releases/tag/v4.0.1" }, { "type": "WEB", "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-13676.json" }, { "type": "WEB", "url": "https://access.redhat.com/errata/RHSA-2026:37186" }, { "type": "WEB", "url": "https://access.redhat.com/errata/RHSA-2026:37585" }, { "type": "WEB", "url": "https://access.redhat.com/errata/RHSA-2026:37628" }, { "type": "WEB", "url": "https://access.redhat.com/errata/RHSA-2026:40118" }, { "type": "WEB", "url": "https://access.redhat.com/errata/RHSA-2026:40262" }, { "type": "WEB", "url": "https://access.redhat.com/errata/RHSA-2026:40765" }, { "type": "WEB", "url": "https://access.redhat.com/errata/RHSA-2026:40945" }, { "type": "WEB", "url": "https://access.redhat.com/errata/RHSA-2026:41066" }, { "type": "WEB", "url": "https://access.redhat.com/errata/RHSA-2026:41928" }, { "type": "WEB", "url": "https://access.redhat.com/errata/RHSA-2026:41929" }, { "type": "WEB", "url": "https://access.redhat.com/errata/RHSA-2026:42815" }, { "type": "WEB", "url": "https://access.redhat.com/errata/RHSA-2026:43038" }, { "type": "WEB", "url": "https://access.redhat.com/errata/RHSA-2026:44239" }, { "type": "WEB", "url": "https://access.redhat.com/errata/RHSA-2026:44268" }, { "type": "WEB", "url": "https://access.redhat.com/errata/RHSA-2026:47728" }, { "type": "WEB", "url": "https://access.redhat.com/errata/RHSA-2026:48124" }, { "type": "WEB", "url": "https://access.redhat.com/errata/RHSA-2026:48126" }, { "type": "WEB", "url": "https://access.redhat.com/errata/RHSA-2026:49642" }, { "type": "WEB", "url": "https://access.redhat.com/errata/RHSA-2026:50340" }, { "type": "WEB", "url": "https://access.redhat.com/errata/RHSA-2026:50479" }, { "type": "WEB", "url": "https://access.redhat.com/errata/RHSA-2026:50758" }, { "type": "WEB", "url": "https://access.redhat.com/errata/RHSA-2026:51196" }, { "type": "WEB", "url": "https://access.redhat.com/errata/RHSA-2026:51197" }, { "type": "WEB", "url": "https://access.redhat.com/errata/RHSA-2026:51342" }, { "type": "WEB", "url": "https://access.redhat.com/errata/RHSA-2026:51348" }, { "type": "WEB", "url": "https://access.redhat.com/errata/RHSA-2026:51349" }, { "type": "WEB", "url": "https://access.redhat.com/errata/RHSA-2026:54760" } ], "schema_version": "1.4.0", "severity": [ { "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N", "type": "CVSS_V3" } ], "summary": "fast-uri vulnerable to host confusion via failed IDN canonicalization" }