fast-uri: fast-uri: Security bypass due to inconsistent host case normalization

A flaw was found in fast-uri, a dependency-free URI parser. This vulnerability occurs because the software folds the host to lowercase before percent-decoding it, allowing percent-encoded uppercase characters to bypass this normalization. A remote attacker could exploit this by crafting a malicio...

CVE-2026-86472 fast-uri vulnerable to inconsistent host case normalization via percent-encoded octets

fast-uri is a dependency-free RFC 3986 URI parser for Node.js, used by Fastify and ajv. In versions before 2.4.7, from 3.0.0 through 3.1.7, and from 4.0.0 through 4.1.4, fast-uri folds the host to lowercase before it percent-decodes the host, so a percent-encoded uppercase octet such as %41 decod...