CVE Watch—

CVE-2021-21166

Google Chromium Race Condition Vulnerability

CVSS

—

No CVSS

EPSS

26.5%

p98

KEV

YES

Nov 3, 2021

Exploit Today

0-100

Published: — · Last modified: —

EPSS · 30d

23.8%EPSS · 30 days26.5%

2026-08-022026-08-31

KEV catalog record

Product

Google / Chromium

Vulnerability

Google Chromium Race Condition Vulnerability

Added to KEV

Nov 3, 2021

Remediate by

Nov 17, 2021

Known ransomware use

Summary description

Google Chromium contains a race condition vulnerability that allows a remote attacker to potentially exploit heap corruption via a crafted HTML page. This vulnerability could affect multiple web browsers that utilize Chromium, including, but not limited to, Google Chrome, Microsoft Edge, and Opera.

Required action

Apply updates per vendor instructions.

Notes

https://nvd.nist.gov/vuln/detail/CVE-2021-21166

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