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.
Affected products
openjsf: fast-uri
References10
- cna.openjsf.org/security-advisories.html Vendor Advisory
- github.com/fastify/fast-uri/security/advisories/GHSA-v39h-62p7-… Vendor Advisory
- access.redhat.com/errata/RHSA-2026:25271
- access.redhat.com/errata/RHSA-2026:25273
- access.redhat.com/errata/RHSA-2026:26225
- access.redhat.com/errata/RHSA-2026:26234
- access.redhat.com/errata/RHSA-2026:28571
- access.redhat.com/errata/RHSA-2026:29197
- access.redhat.com/errata/RHSA-2026:29795
- access.redhat.com/errata/RHSA-2026:29796
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N - EPSS — exploit probability
- 1% percentile: 44 · as of 13 November 2026
- CWE
- CWE-436CWE-140
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