CVE-2021-37973
CriticalExploitedPublic exploitUse after free in Portals in Google Chrome prior to 94.0.4606.61 allowed a remote attacker who had compromised the renderer process to potentially perform a sandbox escape via a crafted HTML page.
Published Dec 15, 2021 · Updated Aug 4, 2026 · Also known as DEBIAN-CVE-2021-37973, TR-21-0776, UBUNTU-CVE-2021-37973
Key Facts
Patch immediately- CVE-2021-37973 is a critical-severity vulnerability (CVSS 9.6 v3.1) affecting Chrome (Google), Debian Linux, Fedora (Fedoraproject) and 18 more products.
- It is exploited in the wild, listed in CISA KEV, Industry KEV feed, CIRCL KEV, ENISA EUVD since Sep 21, 2021. Public exploit code is available.
- EPSS estimates a 12% probability of exploitation in the next 30 days.
- Fixed versions are available, including Chrome 94.0.4606.61, chromedriver 94.0.4606.71-1.1, chromedriver 94.0.4606.71-bp153.2.31.1.
- Brandefense priority: patch immediately, because it is listed as exploited in the wild.
CVSS v3.1
9.6
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
EPSS (30-day exploit likelihood)
12%
Higher than 96.0% of all scored CVEs
Exploited in the wild
Yes
4 catalog listings
Public exploit code
Available
Proof-of-concept or weaponized module
Get the full CVE-2021-37973 brief as a PDF
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Description
Use after free in Portals in Google Chrome prior to 94.0.4606.61 allowed a remote attacker who had compromised the renderer process to potentially perform a sandbox escape via a crafted HTML page.
Known-Exploited Catalog Listings
| Catalog | Added | Remediation due | Ransomware use |
|---|---|---|---|
| CISA KEV | Nov 3, 2021 | Nov 17, 2021 | Not reported |
| Industry KEV feed | Sep 21, 2021 | Nov 17, 2021 | Not reported |
| CIRCL KEV | Nov 3, 2021 | Nov 17, 2021 | Not reported |
| ENISA EUVD | Nov 3, 2021 | n/a | Not reported |
Required action: Apply updates per vendor instructions.
Affected Products
51 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| ChromeGoogle | >= unspecified | 94.0.4606.61 |
| Debian LinuxDebian | 10.0, 11.0 | n/a |
| FedoraFedoraproject | 33, 35 | n/a |
| chromiumarch | See advisory | 94.0.4606.61-1 |
| operaarch | See advisory | 80.0.4170.16-1 |
Patched Releases
Chrome
94.0.4606.61
chromedriver
94.0.4606.71-1.1, 94.0.4606.71-bp153.2.31.1, 94.0.4606.81-lp152.2.132.1
chromium
94.0.4606.61-1, 94.0.4606.71-1.1, 94.0.4606.71-bp153.2.31.1, 94.0.4606.81-lp152.2.132.1, 97.0.4692.71-0.1, 97.0.4692.71-0.1~deb11u1
chromium-browser
94.0.4606.71-0ubuntu0.18.04.1
libqt5-qtpdf-devel
5.15.7-1.1
libqt5-qtpdf-examples
5.15.7-1.1
libqt5-qtpdf-imports
5.15.7-1.1
libqt5-qtpdf-private-headers-devel
5.15.7-1.1
libqt5-qtwebengine
5.15.7-1.1
libqt5-qtwebengine-devel
5.15.7-1.1
libqt5-qtwebengine-examples
5.15.7-1.1
libqt5-qtwebengine-private-headers-devel
5.15.7-1.1
libQt5Pdf5
5.15.7-1.1
libQt5PdfWidgets5
5.15.7-1.1
opera
80.0.4170.16-1
qt5-qtwebengine
5.15.3_git20211006-r1, 5.15.3_git20211006-r3
ungoogled-chromium
113.0.5672.92-1.1
ungoogled-chromium-chromedriver
113.0.5672.92-1.1
vivaldi
4.2.2406.52-1
Timeline
Added to Industry KEV feed
Sep 21, 2021
Added to CISA KEV
Nov 3, 2021
Added to CIRCL KEV
Nov 3, 2021
Added to ENISA EUVD
Nov 3, 2021
Publicly disclosed
Dec 15, 2021
Last updated
Aug 4, 2026
Weakness Type
- CWE-416 Use After Free
References
- advisoryhttps://chromereleases.googleblog.com/2021/12/stable-channel-update-for-desktop_13.html
- advisoryhttps://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-37956
- advisoryhttps://docs.microsoft.com/en-us/DeployEdge/microsoft-edge-relnotes-security#september-24-2021
- advisoryhttps://indianexpress.com/article/technology/tech-news-technology/google-chrome-releases-emergency-update-to-fix-multiple-security-vulnerabilities-7673638/
- advisoryhttps://security-tracker.debian.org/tracker/CVE-2021-37973
FAQ
Common Questions.
Use after free in Portals in Google Chrome prior to 94.0.4606.61 allowed a remote attacker who had compromised the renderer process to potentially perform a sandbox escape via a crafted HTML page.
Affected: Chrome (Google) versions >= unspecified; Debian Linux versions 10.0, 11.0; Fedora (Fedoraproject) versions 33, 35, among others. The full list is in the CVE brief.
It is exploited in the wild, listed in CISA KEV, Industry KEV feed, CIRCL KEV, ENISA EUVD since Sep 21, 2021.
Yes. It was added on Nov 3, 2021 with a federal remediation due date of Nov 17, 2021.
Public exploit code is available.
Fixed versions are available, including Chrome 94.0.4606.61, chromedriver 94.0.4606.71-1.1, chromedriver 94.0.4606.71-bp153.2.31.1.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.
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