Signal is active with 1 mentions in latest observed window
Recommended action window: Monitor and triage in normal cycle
NVD description
fast-uri versions 2.3.1 through 3.1.2 and 4.0.0 fail to canonicalize Unicode (IDN) hostnames for HTTP-family URLs. The IDN conversion path calls a helper that does not exist on the global URL constructor, silently leaving the host in its original Unicode form while normalize() and equal() still return values that differ from a WHATWG-compatible URL parser. Applications that use fast-uri to enforce host-based policy (denylists, loopback filtering, redirect validation, outbound proxy routing) before passing the same URL to Node's URL or fetch can be bypassed when the two implementations resolve the same input to different hosts. Patches: upgrade to fast-uri 3.1.3 for the 3.x line or 4.0.1 for the 4.x line. Workarounds: enforce host policy using the same URL parser used for the actual request, or reject non-ASCII hosts before policy checks.
Priority
LOW
Exploitation
NONE
PoC
NONE
Patch
AVAILABLE
Momentum
STABLE
If you run products in this scope, you should treat this CVE as relevant to your environment.
🚨 High-severity security fix in fast-uri 3.1.3 and 4.0.1 just released! Patches CVE-2026-13676. fast-uri vulnerable to host confusion via failed IDN canonicalization. https://github.com/fastify/fast-uri/security/advisories/GHSA-4c8g-83qw-93j6
Post summary
A security fix for fast‑uri versions 3.1.3 and 4.0.1 has been released, patching CVE‑2026‑13676, a host‑confusion vulnerability caused by poor IDN canonicalization.
🚨 HIGH: CVE-2026-13676 (CVSS 7.5) affects fast-uri 2.3.1-3.1.2 & 4.0.0. Unicode hostname bypass enables policy evasion. Patch to 3.1.3 or 4.0.1 immediately. #CVE #Vulnerability #PatchNow #ThreatIntel https://t.co/p4DoQpyliy
Post summary
CVE‑2026‑13676 is a high‑severity Unicode hostname bypass affecting fast‑uri 2.3.1–3.1.2 and 4.0.0; CVSS 7.5. Patches are available in version 3.1.3 or 4.0.1.
1 of 1 entries
| Part | Vendor | Product | Version | Target SW | Target HW |
|---|---|---|---|---|---|
| App | openjsf | fast-uri | - | node.js | - |