# CVE-2021-37973: Google Chromium Portals Use-After-Free Vulnerability

Source: https://junglewise.ai/threats/cve-2021-37973-google-chromium-portals-use-after-free-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-2021-37973 · Severity: critical · CVSS 9.6 · Exploited in the wild · Published 2021-11-03

A use-after-free vulnerability exists in the Portals component of Google Chromium. A remote attacker who has already compromised the renderer process can exploit this flaw via a crafted HTML page to achieve a sandbox escape.

Vendors: [Google](https://junglewise.ai/threats/vendors/google).

## Quick answers

**Is CVE-2021-37973 exploited in the wild?** Yes. CVE-2021-37973 is known to be exploited in the wild, first recorded on 3 November 2021. Treat it as urgent.

**How severe is CVE-2021-37973?** Critical severity, with a CVSS score of 9.6, published 3 November 2021.

**Which products and versions are affected?** Google Chrome prior to 94.0.4606.61; Microsoft Edge; Google Chromium.

**Is there a fix for CVE-2021-37973?** A patch was published on 2021-09-24: Stable channel update for desktop 94.0.4606.61 released. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2021-37973 attacked?** It is attacked over the network, in a web application.

**Am I affected by CVE-2021-37973?** Check whether you run Google Chromium Portals. 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 94.0.4606.61
- Microsoft Edge
- Google Chromium

## Timeline

- 2021-09-24: patched: Stable channel update for desktop 94.0.4606.61 released.
- 2021-11-03: disclosed: Vulnerability published and added to CISA KEV catalog.
- 2021-11-03: kev added
- 2021-11-03: exploited: Reported as exploited in the wild.