What is CVE-2021-21125?

CVE-2021-21125 is a high-severity vulnerability in Google Chrome, classified under Improper Link Resolution Before File Access. CVSS score: 8.1/10. Published 2021-02-09.

How severe is CVE-2021-21125?

High severity. CVSS v3 base score is 8.1 out of 10.

Vulnerability in Google Chrome

CVE-2021-21125

Insufficient policy enforcement in File System API in Google Chrome on Windows prior to 88.0.4324.96 allowed a remote attacker to bypass filesystem restrictions via a crafted HTML page.

Published 2021-02-09 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N.

EPSS exploit prediction

EPSS: 0.081 (94.6th percentile), scored 2026-10-01.

Low probability of exploitation in the next 30 days, but still tracked. 95th percentile — 94.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.081 · newest: 0.081 · change: 0.000

Affected products

Google Chrome — versions unspecified
Microsoft Edge Chromium

Weakness classification (CWE)

CWE-59 — Improper Link Resolution Before File Access

References

chromereleases.googleblog.com/2021/01/stable-channel-update-for-desktop_19.html (Release Notes, Vendor Advisory)
crbug.com/1152327 (Permissions Required, Third Party Advisory)
msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2021-21125 (Third Party Advisory)

Frequently asked questions

What is CVE-2021-21125?: CVE-2021-21125 is a high-severity vulnerability in Google Chrome, classified under Improper Link Resolution Before File Access. CVSS score: 8.1/10. Published 2021-02-09.
How severe is CVE-2021-21125?: High severity. CVSS v3 base score is 8.1 out of 10.