What is CVE-2025-21404?

CVE-2025-21404 is a medium-severity vulnerability in Microsoft Edge Chromium, classified under CWE-449. CVSS score: 4.3/10. Published 2025-02-06.

How severe is CVE-2025-21404?

Medium severity. CVSS v3 base score is 4.3 out of 10.

Vulnerability in Microsoft Edge Chromium

CVE-2025-21404

Microsoft Edge (Chromium-based) Spoofing Vulnerability

Published 2025-02-06 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 4.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N.

EPSS exploit prediction

EPSS: 0.011 (64.0th percentile), scored 2026-09-30.

Low probability of exploitation in the next 30 days, but still tracked. 64th percentile — 64.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.011 · newest: 0.011 · change: 0.000

Affected products

Microsoft Edge Chromium
Microsoft Edge (Chromium-Based) — versions 1.0.0.0

Weakness classification (CWE)

References

msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21404 (vendor-advisory, patch, Vendor Advisory)

Frequently asked questions

What is CVE-2025-21404?: CVE-2025-21404 is a medium-severity vulnerability in Microsoft Edge Chromium, classified under CWE-449. CVSS score: 4.3/10. Published 2025-02-06.
How severe is CVE-2025-21404?: Medium severity. CVSS v3 base score is 4.3 out of 10.