remix-run react-router API getKey/storageKey cross site scripting

CVSS Meta Temp Score
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CTI Interest Score
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6.1$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as problematic, was found in remix-run react-router. This impacts an unknown function of the component API. Executing a manipulation of the argument getKey/storageKey can lead to cross site scripting. This vulnerability is handled as CVE-2026-21884. The attack can be executed remotely. There is not any exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic was found in remix-run react-router (affected version not known). This vulnerability affects some unknown functionality of the component API. The manipulation of the argument getKey/storageKey with an unknown input leads to a cross site scripting vulnerability. The CWE definition for the vulnerability is CWE-79. The product 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. As an impact it is known to affect integrity. CVE summarizes:

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.

The advisory is available at github.com. This vulnerability was named CVE-2026-21884 since 01/05/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. Successful exploitation requires user interaction by the victim. Technical details are known, but there is no available exploit. This vulnerability is assigned to T1059.007 by the MITRE ATT&CK project.

The vulnerability scanner Nessus provides a plugin with the ID 282620 (Linux Distros Unpatched Vulnerability : CVE-2026-21884), which helps to determine the existence of the flaw in a target environment.

Upgrading eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (282620) and EUVD (EUVD-2026-1466). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

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Vendor

Name

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.2
VulDB Meta Temp Score: 6.1

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 8.2
CNA Vector (GitHub_M): 🔒

CVSSv2info

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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Cross site scripting
CWE: CWE-79 / CWE-94 / CWE-74
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 282620
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2026-21884

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Timelineinfo

01/05/2026 CVE reserved
01/10/2026 +5 days Advisory disclosed
01/10/2026 +0 days VulDB entry created
01/13/2026 +3 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: GHSA-8v8x-cx79-35w7
Status: Confirmed

CVE: CVE-2026-21884 (🔒)
GCVE (CVE): GCVE-0-2026-21884
GCVE (VulDB): GCVE-100-340426
EUVD: 🔒

Entryinfo

Created: 01/10/2026 10:42
Updated: 01/13/2026 23:45
Changes: 01/10/2026 10:42 (66), 01/10/2026 11:15 (1), 01/11/2026 01:49 (1), 01/13/2026 23:45 (2)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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