# CVE-2021-21166: Google Chromium Race Condition Vulnerability

Source: https://junglewise.ai/threats/cve-2021-21166-google-chromium-race-condition-vulnerability  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2021-11-03. Updated: 2026-05-10  
License: CC BY 4.0 with a link back

CVE-2021-21166 · Severity: critical · CVSS 8.8 · Exploited in the wild · Published 2021-11-03

A race condition in the audio component of Google Chromium allows a remote attacker to potentially cause heap corruption via a specially crafted HTML page. This vulnerability has been observed being exploited in the wild and affects multiple Chromium-based browsers.

Technologies: [Google Chromium](https://junglewise.ai/threats/technologies/chromium). Vendors: [Google](https://junglewise.ai/threats/vendors/google).

## Quick answers

**Is CVE-2021-21166 exploited in the wild?** Yes. CVE-2021-21166 is known to be exploited in the wild, first recorded on 3 November 2021. Treat it as urgent.

**How severe is CVE-2021-21166?** Critical severity, with a CVSS score of 8.8, published 3 November 2021.

**Which products and versions are affected?** Google Chrome prior to 89.0.4389.72; Microsoft Edge; Opera Opera.

**Is there a fix for CVE-2021-21166?** A patch was published on 2021-03-02: Chrome version 89.0.4389.72 released to address the issue. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2021-21166 attacked?** It is attacked over the network, in a web application.

**Am I affected by CVE-2021-21166?** Check whether you run Google Chromium. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Affected products

- Google Chrome prior to 89.0.4389.72
- Microsoft Edge
- Opera Opera

## Timeline

- 2021-03-02: patched: Chrome version 89.0.4389.72 released to address the issue.
- 2021-11-03: kev added: Added to CISA's Known Exploited Vulnerabilities Catalog.
- 2021-11-03: disclosed

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