CVE-2018-6342: Facebook React-Dev-Utils

Critical severity, CVSS 9.8. EPSS: 2.8% chance of exploitation in the next 30 days.

react-dev-utils on Windows allows developers to run a local webserver for accepting various commands, including a command to launch an editor. The input to that command was not properly sanitized, allowing an attacker who can make a network request to the server (either via CSRF or by direct request) to execute arbitrary commands on the targeted system. This issue affects multiple branches: 1.x.x prior to 1.0.4, 2.x.x prior to 2.0.2, 3.x.x prior to 3.1.2, 4.x.x prior to 4.2.2, and 5.x.x prior to 5.0.2.

Affected products

• Facebook React-Dev-Utils: from 1.0.0, before 1.0.4 (fixed in 1.0.4); from 2.0.0, before 2.0.2 (fixed in 2.0.2); from 3.0.0, before 3.1.2 (fixed in 3.1.2); from 4.0.0, before 4.2.2 (fixed in 4.2.2); from 5.0.0, before 5.0.2 (fixed in 5.0.2)

Published 2018-12-31. Last modified 2026-06-17.