CVE-2026-6322

A flaw was found in fast-uri. A remote attacker could exploit this vulnerability by crafting a malicious Uniform Resource Identifier (URI) that contains percent-encoded authority delimiters. The fast-uri library incorrectly decodes these delimiters during normalization and then re-emits them as raw separators, which can change the URI's intended authority. This issue allows applications that perform host allowlist checks, redirect validation, or outbound request routing to be steered to a different authority than specified, potentially bypassing security controls.

This Important flaw in the fast-uri library allows an attacker to bypass security controls in Red Hat products that process Uniform Resource Identifiers (URIs). By crafting a malicious URI with percent-encoded authority delimiters, an attacker can cause the library to incorrectly interpret the URI's authority, potentially redirecting applications to an unintended domain. This could lead to a bypass of host allowlist checks, redirect validation, or outbound request routing.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.