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Fencer Vulns
medium 6.1

CVE-2026-110306 json

fast-uri vulnerable to URI scheme spoofing via percent-encoded scheme decoding

published 2026-10-20 20 d ago modified 2026-10-23 16 d ago also EUVD-2026-104814 , GHSA-w74x-v6f9-j3xg

cvss
6.1
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.3%
EPSS 0.3% chance of exploitation in 30 days, percentile 16%
public exploits
0
none known

Summary

fast-uri is a dependency-free RFC 3986 URI parser and serializer for Node.js. In versions before 2.4.8, from 3.0.0 through 3.1.8, and from 4.0.0 through 4.2.2, fast-uri percent-decodes the scheme component with the legacy global unescape() function before validating it, so an input whose decoded scheme is a dangerous token is emitted as a live scheme even though RFC 3986 does not allow percent-encoding in a scheme and no other parser accepts it. An application that screens dangerous schemes on the raw input and then stores or renders the normalized or resolved result can turn an inert string into an executable javascript, data, or vbscript URL, producing a stored or reflected cross-site scripting vector, and the equal() comparison treats an encoded and a plain scheme as the same, which can bypass equality-based allowlists. The issue is fixed in fast-uri 2.4.8, 3.1.9, and 4.2.3, and users should upgrade to one of these versions or later. As a workaround, reject input whose scheme part contains a percent sign, or check the parsed scheme against an allowlist after normalization and use that same parsed result rather than the raw string.

Patch / fix

  • npm fast-uri 2.4.8, 3.1.9, 4.2.3
  • fast-uri fast-uri 2.4.8, 3.1.9, 4.2.3
  • node-ajv Debian 14 8.20.0~ds+~cs7.2.4-1

debian advisories DEBIAN-CVE-2026-110306

  • git-bug openSUSE Tumbleweed 0.11.0-3.1

opensuse advisories openSUSE-SU-2026:12261-1

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-110306 updated cvss 6.1

fast-uri: fast-uri: Cross-Site Scripting via improper URI scheme decoding

  • Red Hat Cost Management On Premise costmanagement/costmanagement-ui-rhel10 Red Hat Cryostat 4 cryostat/cryostat-openshift-console-plugin-rhel9 Red Hat Migration Toolkit for Applications 8 mta/mta-solution-server-rhel9 Red Hat Multicluster Engine for Kubernetes multicluster-engine/console-mce-rhel9 Red Hat Network Observability Operator network-observability/network-observability-console-plugin-rhel9, network-observability/network-observability-console-plugin-pf5-rhel9 Red Hat OpenShift Lightspeed openshift-lightspeed/lightspeed-console-plugin-rhel9, openshift-lightspeed/lightspeed-agentic-console-rhel9, openshift-lightspeed/lightspeed-console-plugin-419-rhel9, openshift-lightspeed/lightspeed-console-plugin-pf5-rhel9
    +4 more products
    Red Hat OpenShift Pipelines openshift-pipelines/pipelines-hub-ui-rhel8, openshift-pipelines/pipelines-hub-ui-rhel9 Red Hat OpenShift Serverless openshift-serverless-1/kn-eventing-integrations-transform-jsonata-rhel9 Red Hat Advanced Cluster Management for Kubernetes 2 rhacm2/console-rhel9 Red Hat AMQ Broker 7 amq-broker-bin.zip 7.14.1.CR3, amq-broker-maven-repository.zip 7.14.1.CR3
    affected: no fix available “Fix deferred”
  • Red Hat Ansible Automation Platform 2 automation-platform-ui 2.6.15-1.el9ap, automation-gateway 2.5.20260923-1.el9ap, ansible-automation-platform-24/lightspeed-rhel8, ansible-automation-platform-27/mcp-server-rhel9, ansible-automation-platform-tech-preview/mcp-server-rhel9
    affected: no fix available, no fix planned “Out of support scope”
  • Red Hat build of Apache Camel - HawtIO 4 rhaf-hawtio-maven-repository.zip 4.4.0.GA Red Hat Build of Podman Desktop rh-podman-desktop 3c6fc75a2a6cf5bb9b8a667fddcbbf428132badc Red Hat Data Grid 8 redhat-datagrid-maven-repository.zip 8.6.1.CR1 Red Hat Developer Hub 1 rhdh/rhdh-hub-rhel9, rhdh/red-hat-developer-hub-backstage-plugin-orchestrator, rhdh/red-hat-developer-hub-backstage-plugin-lightspeed-backend, rhdh/red-hat-developer-hub-backstage-plugin-orchestrator-backend, rhdh/red-hat-developer-hub-backstage-plugin-orchestrator-form-widgets, rhdh/red-hat-developer-hub-backstage-plugin-orchestrator-backend-module-loki, +1 more
    affected: no fix available “Fix deferred”
  • Red Hat Directory Server 11 389-ds-base 1.4.3.34-18.module+el8dsrv+24812+0acb1821 Red Hat Directory Server 12 389-ds-base 2.2.7-18.module+el9dsrv+24814+6d9b6eb5
    affected: no fix planned “Out of support scope”
  • Red Hat Discovery 2 discovery/discovery-ui-rhel9 Red Hat Edge Manager 1 rhem/flightctl-ui-rhel9, rhem/flightctl-ui-rhel10, rhem/flightctl-ui-ocp-rhel9, rhem/flightctl-ui-ocp-rhel10 Red Hat Enterprise Linux 8 dotnet, dotnet-host, dotnet-sdk-8.0, dotnet-hostfxr-8.0, dotnet-runtime-8.0, dotnet-sdk-dbg-8.0, +10 more Red Hat Enterprise Linux 9 sgx-mpa, tdx-qgs, sgx-libs, sgx-pccs, sgx-common, dotnet-host, +17 more Red Hat Enterprise Linux 10 grafana 12.4.3-2.el10, linux-sgx 2.26-7.el10, dotnet8.0 8.0.130-2.el10, grafana-pcp 6.1.0-1.el10, cockpit-image-builder 110.1-1.el10_3 Red Hat Enterprise Linux AI (RHEL AI) 3 rhelai3/bootc-cuda-rhel9, rhelai3/bootc-rocm-rhel9, rhelai3/bootc-gaudi-rhel9, rhelai3/disk-image-cuda-rhel9
    +3 more products
    Red Hat OpenShift AI (RHOAI) rhoai/odh-core-bff-rhel9, rhoai/odh-dashboard-rhel9, rhoai/odh-mod-arch-maas-rhel9, rhoai/odh-feature-server-rhel9, rhoai/odh-mod-arch-automl-rhel9, rhoai/odh-mod-arch-gen-ai-rhel9, +7 more Red Hat OpenShift Container Platform 4 openshift4/ose-console-rhel9, openshift4/ose-monitoring-plugin-rhel9, openshift4/nmstate-console-plugin-rhel9 Red Hat OpenShift Container Platform 5 openshift5/ose-console-rhel9, openshift5/ose-monitoring-plugin-rhel9, openshift5/nmstate-console-plugin-rhel9
    affected: no fix available “Fix deferred”
  • Red Hat Openshift Data Foundation 4 odf4/mcg-core-rhel9, odf4/odf-console-rhel9, odf4/ocs-client-console-rhel9, odf4/odf-multicluster-console-rhel9
    affected: no fix available, no fix planned “Out of support scope”
  • Red Hat OpenShift Dev Spaces devspaces/code-rhel9, devspaces/openvsx-rhel9, devspaces/dashboard-rhel9, devspaces/pluginregistry-rhel9
    affected: no fix available “Fix deferred”
  • Red Hat Quay 3 quay/quay-rhel8, quay/quay-rhel9
    affected: no fix planned “Out of support scope”
show 5 more
  • Red Hat Satellite 6 nodejs-webpack 5.109.2-1.el10sat, satellite/iop-remediations-rhel9, satellite/iop-advisor-frontend-rhel9, satellite/iop-vulnerability-frontend-rhel9, satellite/iop-host-inventory-frontend-rhel9, nodejs-mini-css-extract-plugin 2.10.2-2.2.el10sat, +1 more
    affected: no fix available “Fix deferred”
  • Red Hat Secrets Management Console for Red Hat OpenShift external-secrets-management/console-plugin-rhel9
    affected: no fix planned “Out of support scope”
  • Red Hat Self-service automation portal 2 ansible-automation-platform/automation-portal, ansible-automation-platform/bootc-automation-portal-rhel9
    affected: no fix available “Fix deferred”
  • Red Hat Hardened Images grafana13.1 13.1.8-0.5.hum1, grafana13.2 13.2.4-0.4.hum1, grafana12.4 12.4.13-0.4.hum1, grafana12.4 12.4.13-0.5.hum1
    fixed: vendor fix RHSA-2026:90388
  • Red Hat Hardened Images dotnet8.0 8.0.130-2.el10, prometheus3.13 3.13.4-0.1.hum1
    not affected: component not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
19 d ago

Exploit prediction

0.25% chance of exploitation in the next 30 days, higher than 16% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.1 6.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
GitHub 3.1 6.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Affected packages

ecosystem package affected fixed in
npm fast-uri
<2.4.8
>=3.0.0, <3.1.9
>=4.0.0, <4.2.3
2.4.8
3.1.9
4.2.3

Affected products

  • fast-uri fast-uri

Classification

Weakness
  • CWE-172 Improper Encoding or Decoding of Data
  • CWE-180 Incorrect Behavior Order: Validate Before Canonicalize

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.