CVE-2026-6322
fast-uri vulnerable to host confusion via percent-encoded authority delimiters
Description
fast-uri normalize() decoded percent-encoded authority delimiters inside the host component and then re-emitted them as raw delimiters during serialization. A host that combined an allowed domain, an encoded at-sign, and a different domain was re-emitted with the at-sign as a raw userinfo separator, changing the URI's authority to the second domain. Applications that normalize untrusted URLs before host allowlist checks, redirect validation, or outbound request routing can be steered to a different authority than the input appeared to specify. Versions <= 3.1.1 are affected. Update to 3.1.2 or later.
How to fix CVE-2026-6322
To remediate CVE-2026-6322, upgrade the affected package to a fixed version below.
- —no fix listed
- —upgrade to 3.1.2 or later
Is CVE-2026-6322 being exploited?
Low — EPSS is 0.0%, meaning exploitation activity has not been observed at scale.
Affected packages (2)
- from 0
- from 0, < 3.1.2
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | HIGH7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N |