VDB-368057 · CVE-2026-42211 · GHSA-49rj-9fvp-4h2h

remix-run react-router up to 7.14.1 createBrowserRouter/ deserialization

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
6.7	$0-$5k	0.00

Summaryinfo

A vulnerability marked as problematic has been reported in remix-run react-router up to 7.14.1. This affects an unknown function of the file createBrowserRouter/. The manipulation leads to deserialization. This vulnerability is uniquely identified as CVE-2026-42211. The attack is possible to be carried out remotely. No exploit exists. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in remix-run react-router up to 7.14.1. This issue affects an unknown code of the file createBrowserRouter/. The manipulation with an unknown input leads to a deserialization vulnerability. Using CWE to declare the problem leads to CWE-502. The product deserializes untrusted data without sufficiently verifying that the resulting data will be valid. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

React Router is a router for React. In versions 7.0.0 through 7.14.1, when using Framework Mode, a combination of steps could potentially allow unauthorized remote code execution (RCE) through external requests. This attack requires the application code to have an existing prototype pollution vulnerability, which can then be leveraged in a 2-step attack where the second step triggers unauthorized RCE on the remote server. This does not impact applications using Declarative Mode (``) or Data Mode (`createBrowserRouter/`). This is patched in version 7.14.2.

The advisory is shared at github.com. The identification of this vulnerability is CVE-2026-42211 since 04/25/2026. The exploitation is known to be difficult. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Technical details are known, but no exploit is available.

Upgrading to version 7.14.2 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-33999). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

Router Operating System

Vendor

remix-run

Name

react-router

Version

Website

Product: https://github.com/remix-run/react-router/

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.8
VulDB Meta Temp Score: 6.7

VulDB Base Score: 5.6
VulDB Temp Score: 5.4
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 8.1
CNA Vector (GitHub_M): 🔒

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

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

Exploitinginfo

Class: Deserialization
CWE: CWE-502 / CWE-20
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: react-router 7.14.2

Timelineinfo

04/25/2026 CVE reserved
06/02/2026 +38 days VulDB entry created
06/03/2026 +0 days Advisory disclosed
06/04/2026 +1 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: GHSA-49rj-9fvp-4h2h
Status: Confirmed

CVE: CVE-2026-42211 (🔒)
GCVE (CVE): GCVE-0-2026-42211
GCVE (VulDB): GCVE-100-368057
EUVD: 🔒

Entryinfo

Created: 06/03/2026 01:42
Updated: 06/04/2026 04:40
Changes: 06/03/2026 01:42 (65), 06/04/2026 04:40 (1)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.