CVE-2018-6342

Severity: critical (CVSS 9.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 2.8% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2018-12-31 · updated 2026-06-17
Weakness: CWE-78

Description

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; from 2.0.0 before 2.0.2; from 3.0.0 before 3.1.2; from 4.0.0 before 4.2.2; from 5.0.0 before 5.0.2 — fixed in 1.0.4, 2.0.2, 3.1.2, 4.2.2, 5.0.2

How to fix

Upgrade to a fixed version: Facebook react-dev-utils 1.0.4, 2.0.2, 3.1.2, 4.2.2. Check the vendor advisory for mitigations.

References

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