Auth bypass in Facebook React-Devtools

CVE-2023-5654

The React Developer Tools extension registers a message listener with window.addEventListener('message', <listener>) in a content script that is accessible to any webpage that is active in the browser. Within the listener is code that requests a URL derived from the received message via fetch(). The URL is not validated or sanitised before it is fetched, thus allowing a malicious web page to arbitrarily fetch URL’s via the victim's browser.

EPSS: 0.005 (37.9th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2023-5654?
CVE-2023-5654 is a medium-severity vulnerability in Facebook React-Devtools, classified under Improper Authorization. CVSS score: 6.5/10. Published 2023-10-19.
How severe is CVE-2023-5654?
Medium severity. CVSS v3 base score is 6.5 out of 10.