IRONSMITHINTEL
HIGHCVSS8.8
|
Actively Exploited
|CISA KEV|CVE-2021-21224|Auth: none — unauthenticated|Reboot: required|Manual only

Google Chromium V8 Type Confusion Vulnerability

Google Chromium V8 Engine contains a type confusion vulnerability that allows a remote attacker to execute code inside a sandbox 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.

Published Apr 26, 2021 · Updated May 16, 2026
Why patchRisk explained in plain English
Worst-case scenarioIf unpatched

A remote attacker, without authentication, can achieve full data confidentiality loss, arbitrary modification of data, complete denial of service or system unavailability. Federal agencies are required to remediate by 2021-11-17 under CISA BOD 22-01.

How the attack worksNo clicks needed

This is a Type Confusion (CWE-843) vulnerability in Google Chromium V8. Type confusion in V8 in Google Chrome prior to 90.0.4430.85 allowed a remote attacker to execute arbitrary code inside a sandbox via a crafted HTML page. Exploitation requires remote network access, low attack complexity, no authentication required, and user interaction required.

📧

Phishing link

🖼

Malicious file

🔓

Server compromised

Am I affected?Quick check

Probably yes if any of these apply:

IT Security
Running chrome: v < 90.0.4430.85; debian linux: 10.0; fedora: 32, 33, 34
Real-world incidentsWhat we've seen

Active exploitation documented in the wild. Threat-research write-up: https://crbug.com/1195777

How to patch

Manual remediation steps

Apply the Vendor Patch

This vulnerability is in the CISA Known Exploited Vulnerabilities catalog — apply the vendor's security update as soon as possible.

CISA required action: Apply updates per vendor instructions.

References

    1
    NVD entry: https://nvd.nist.gov/vuln/detail/CVE-2021-21224
    1
    CISA KEV: https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-21224
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