--- id: CVE-2026-6321 title: >- fast-uri decoded percent-encoded path separators and dot segments before applying dot-segment removal in its normalize() and equal() functions summary: >- fast-uri decoded percent-encoded path separators and dot segments before applying dot-segment removal in its normalize() and equal() functions. Encoded path data was treated like real slashes and parent-directory references, so distinct … severity: high cvss: 7.5 cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N' cwe: - CWE-22 vendor: openjsf product: fast-uri affected: - fast-uri < 3.1.1 patched: - fast-uri 3.1.1 published: '2026-05-04' updated: '2026-09-10' sourceUpdated: '2026-09-10T13:20:28.160' source: NVD sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-6321' references: - url: 'https://cna.openjsf.org/security-advisories.html' label: ce714d77-add3-4f53-aff5-83d477b104bb - url: >- https://github.com/fastify/fast-uri/security/advisories/GHSA-q3j6-qgpj-74h6 label: ce714d77-add3-4f53-aff5-83d477b104bb - url: 'https://access.redhat.com/errata/RHSA-2026:19238' label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c - url: 'https://access.redhat.com/errata/RHSA-2026:20338' label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c - url: 'https://access.redhat.com/errata/RHSA-2026:21338' label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c - url: 'https://access.redhat.com/errata/RHSA-2026:24473' label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c - url: 'https://access.redhat.com/errata/RHSA-2026:24766' label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c - url: 'https://access.redhat.com/errata/RHSA-2026:24866' label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c - url: 'https://access.redhat.com/errata/RHSA-2026:24977' label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c - url: 'https://access.redhat.com/errata/RHSA-2026:25089' label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c - url: 'https://access.redhat.com/errata/RHSA-2026:25123' label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c - url: 'https://access.redhat.com/errata/RHSA-2026:26214' label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c - url: 'https://access.redhat.com/errata/RHSA-2026:26234' label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c - url: 'https://access.redhat.com/errata/RHSA-2026:26416' label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c - url: 'https://access.redhat.com/errata/RHSA-2026:26420' label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c - url: 'https://access.redhat.com/errata/RHSA-2026:34342' label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c - url: 'https://access.redhat.com/errata/RHSA-2026:37385' label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c - url: 'https://access.redhat.com/errata/RHSA-2026:42078' label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c - url: 'https://access.redhat.com/errata/RHSA-2026:42079' label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c - url: 'https://access.redhat.com/errata/RHSA-2026:56366' label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c - url: 'https://access.redhat.com/errata/RHSA-2026:56431' label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c - url: 'https://access.redhat.com/errata/RHSA-2026:56928' label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c - url: 'https://access.redhat.com/errata/RHSA-2026:57013' label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c - url: 'https://access.redhat.com/security/cve/CVE-2026-6321' label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2466582' label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c - url: >- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-6321.json label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c - url: 'https://www.cve.org/CVERecord?id=CVE-2026-6321' - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-6321' tags: - nvd - cve.org - csaf - vex - red-hat ssvc: exploitation: none automatable: 'yes' technicalImpact: partial timestamp: '2026-05-05T12:44:27.336265Z' epss: 0.00765 epssPercentile: 0.53535 ingestedAt: '2026-07-02T12:34:40.543Z' --- ## Overview fast-uri decoded percent-encoded path separators and dot segments before applying dot-segment removal in its normalize() and equal() functions. Encoded path data was treated like real slashes and parent-directory references, so distinct URIs could collapse onto the same normalized path. Applications that normalize or compare attacker-controlled URLs to enforce path-based policy can be bypassed, with a path that appears confined under an allowed prefix normalizing to a different location. Versions <= 3.1.0 are affected. Update to 3.1.1 or later. ## Affected - `fast-uri < 3.1.1` ## Remediation Upgrade past the affected range: - `fast-uri 3.1.1` ## Vendor advisories - **RHSA-2026:42078** · Red Hat · fixed in: Red Hat Ansible Automation Platform 2.5 for RHEL 8, Red Hat Ansible Automation Platform 2.5 for RHEL 9 · released 2026-07-20 · [advisory](https://access.redhat.com/errata/RHSA-2026:42078) - **RHSA-2026:42079** · Red Hat · fixed in: Red Hat Ansible Automation Platform 2.6 for RHEL 9 · released 2026-07-20 · [advisory](https://access.redhat.com/errata/RHSA-2026:42079) - **RHSA-2026:34342** · Red Hat · fixed in: Cluster Observability Operator 1.5.0 · released 2026-07-01 · [advisory](https://access.redhat.com/errata/RHSA-2026:34342) - **RHSA-2026:37385** · Red Hat · fixed in: Red Hat Enterprise Linux Extensions Channel (v. 10) · released 2026-07-09 · [advisory](https://access.redhat.com/errata/RHSA-2026:37385) - **RHSA-2026:25089** · Red Hat · fixed in: HawtIO HawtIO 4.4.0 · released 2026-06-10 · [advisory](https://access.redhat.com/errata/RHSA-2026:25089) - **RHSA-2026:24473** · Red Hat · fixed in: Network Observability (NETOBSERV) 1.12.2 · released 2026-06-08 · [advisory](https://access.redhat.com/errata/RHSA-2026:24473) - **RHSA-2026:24766** · Red Hat · fixed in: Red Hat Ansible Automation Platform 2.5 · released 2026-06-09 · [advisory](https://access.redhat.com/errata/RHSA-2026:24766) - **RHSA-2026:24866** · Red Hat · fixed in: Red Hat Ansible Automation Platform 2.6 · released 2026-06-09 · [advisory](https://access.redhat.com/errata/RHSA-2026:24866) - **RHSA-2026:21338** · Red Hat · fixed in: Red Hat Developer Hub 1.8 · released 2026-05-27 · [advisory](https://access.redhat.com/errata/RHSA-2026:21338) - **RHSA-2026:26234** · Red Hat · fixed in: Red Hat Developer Hub 1.9 · released 2026-06-16 · [advisory](https://access.redhat.com/errata/RHSA-2026:26234) - **RHSA-2026:20338** · Red Hat · fixed in: Red Hat Discovery 2 · released 2026-05-21 · [advisory](https://access.redhat.com/errata/RHSA-2026:20338) - **Red Hat VEX** · Important · affected: Confidential Compute Attestation, OpenShift Pipelines, Red Hat Ansible Automation Platform 2, Red Hat Build of Podman Desktop, Red Hat Build of Podman Desktop - Tech Preview, Red Hat Data Grid 8, … · no fix planned: Red Hat Developer Hub, Confidential Compute Attestation, OpenShift Pipelines, Red Hat Ansible Automation Platform 2, … · updated 2026-09-24 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-6321.json)