Interpretation Conflict in fast-uri - CVE-2026-13676

Vulnerability identifier: #VU138918

CSH Severity: High

CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-13676

CWE-ID: CWE-436

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote attacker to modify data on the system.

The vulnerability exists due to fast-uri fail to canonicalize Unicode (IDN) hostnames for HTTP-family URLs. The IDN conversion path calls a helper that does not exist on the global URL constructor, silently leaving the host in its original Unicode form while normalize() and equal() still return values that differ from a WHATWG-compatible URL parser. A remote attacker can trigger the vulnerability to modify data on the system.

fast-uri
MongoDB Enterprise Advanced with IBM
IBM Maximo Application Suite - Manage Component
Bitbucket Data Center
Bamboo Data Center
Ansible Automation Platform
Red Hat OpenShift Container Platform

Install updates from vendor's website.

fast-uri - addressed in versions 2.4.2, 3.1.3, 4.0.1
IBM Maximo Application Suite - Manage Component - addressed in versions 9.0.28, 9.1.20, 9.2.1
Bitbucket Data Center - update to 9.4.23
Bamboo Data Center - update to 10.2.22
MongoDB Enterprise Advanced with IBM - update to 1.49.11
Ansible Automation Platform - update to 2.2.0
Red Hat OpenShift Container Platform - addressed in versions 4.19.39, 4.20.29, 4.21.24, 4.21.26

• https://cna.openjsf.org/security-advisories.html
• https://github.com/fastify/fast-uri/security/advisories/GHSA-4c8g-83qw-93j6
• https://access.redhat.com/errata/RHSA-2026:37186
• https://access.redhat.com/errata/RHSA-2026:37585
• https://access.redhat.com/errata/RHSA-2026:37628
• https://access.redhat.com/errata/RHSA-2026:40118
• https://access.redhat.com/errata/RHSA-2026:40262
• https://access.redhat.com/errata/RHSA-2026:40945
• https://access.redhat.com/errata/RHSA-2026:41066
• https://access.redhat.com/security/cve/CVE-2026-13676
• https://bugzilla.redhat.com/show_bug.cgi?id=2494197
• https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-13676.json

• Interpretation Conflict in fast-uri
• Multiple vulnerabilities in Red Hat OpenShift Container Platform 4.21
• Multiple vulnerabilities in Red Hat OpenShift Container Platform 4.20
• Multiple vulnerabilities in Red Hat OpenShift Container Platform 4.19
• Multiple vulnerabilities in Red Hat OpenShift Container Platform 4.21
• Multiple vulnerabilities in IBM Maximo Application Suite - Manage Component
• Multiple vulnerabilities in Ansible Automation Platform 2.2 packages
• Multiple vulnerabilities in Bamboo Data Center
• Multiple vulnerabilities in Bitbucket Data Center
• MongoDB Enterprise Advanced with IBM update for fast-uri