XSS: <ScrollRestoration> SSR in @remix-run/react, react-router <7.12 Pre-2.17.3
CVE-2026-21884 Published on January 10, 2026

React Router SSR XSS in ScrollRestoration
React Router is a router for React. In @remix-run/react version prior to 2.17.3. and react-router 7.0.0 through 7.11.0, a XSS vulnerability exists in in React Router's <ScrollRestoration> API in Framework Mode when using the getKey/storageKey props during Server-Side Rendering which could allow arbitrary JavaScript execution during SSR if untrusted content is used to generate the keys. There is no impact if server-side rendering in Framework Mode is disabled, or if Declarative Mode (<BrowserRouter>) or Data Mode (createBrowserRouter/<RouterProvider>) is being used. This issue has been patched in @remix-run/react version 2.17.3 and react-router version 7.12.0.

Github Repository NVD

Vulnerability Analysis

CVE-2026-21884 is exploitable with network access, requires user interaction. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to have a high impact on confidentiality, with no impact on integrity, and no impact on availability.

Attack Vector:
NETWORK
Attack Complexity:
LOW
Privileges Required:
NONE
User Interaction:
REQUIRED
Scope:
CHANGED
Confidentiality Impact:
HIGH
Integrity Impact:
LOW
Availability Impact:
NONE

Weakness Type

What is a XSS Vulnerability?

The software does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.

CVE-2026-21884 has been classified to as a XSS vulnerability or weakness.


Products Associated with CVE-2026-21884

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Red Hat Ansible Automation Platform
 
Red Hat Ansible Automation Platform Developer
 
Red Hat Ansible Automation Platform Inside
 
Red Hat Openshift Ai
 
Red Hat Kueue Operator
 
Red Hat Enterprise Linux (RHEL)
 

Affected Versions

remix-run react-router: Red Hat Ansible Automation Platform 2.6 for RHEL 9: Red Hat Ansible Automation Platform 2.6: Red Hat OpenShift AI 2.25: Red Hat OpenShift AI 3.3: Red Hat Ansible Automation Platform 2.6 for RHEL 10: Red Hat Build of Kueue: Red Hat Enterprise Linux 10: Red Hat Enterprise Linux 9:

Vulnerable Packages

The following package name and versions may be associated with CVE-2026-21884

Package Manager Vulnerable Package Versions Fixed In
npm react-router >= 7.0.0, < 7.12.0 7.12.0
npm @remix-run/react < 2.17.3 2.17.3

Exploit Probability

EPSS
0.37%
Percentile
28.25%

EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.