CVE-2026-6322
Description
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.
Statement
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.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 7.5 | N/A | 7.5 |
| Attack Vector | Network | N/A | Network |
| Attack Complexity | Low | N/A | Low |
| Privileges Required | None | N/A | None |
| User Interaction | None | N/A | None |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | None | N/A | None |
| Integrity Impact | High | N/A | High |
| Availability Impact | None | N/A | None |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
cve.org: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Understanding the Weakness (CWE)
Integrity
Technical Impact: Unexpected State
Frequently Asked Questions
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