Exploited CVEs / Google / CVE-2021-37976

CVE-2021-37976

Google Chromium Information Disclosure Vulnerability. Exploitation in the wild is confirmed by CISA, not predicted. Federal agencies were required to remediate by 2021-11-17 (that deadline has passed); treat that date as the outer bound for your own environment. The fix is in the vendor advisory: Chrome Releases (security updates), linked below.

Risk summary

MediumCISA KEV
6.5
CVSS base
20%
EPSS exploit probability
Medium
Severity
2021-11-03
Added to KEV
2021-11-17 (past due)
CISA due date

Actively exploited Google Chromium vulnerability, Medium severity, CVSS 6.5. Added to the CISA KEV catalog 2021-11-03.

Senserva AI read on CVE-2021-37976CISA required actionOfficial fix for CVE-2021-37976Admin questions

Senserva AI Opinion for CVE-2021-37976

This is a memory information disclosure flaw in Chromium's core memory component that leaks sensitive data from process memory when a user opens a crafted HTML page, and because Chromium is the shared engine, it affects Chrome plus Edge, Brave, Opera and other derivatives. CISA confirmed active exploitation and added it to the KEV catalog on 2021-11-03, so despite the Medium (CVSS 6.5) rating this is a real in-the-wild target. Leaked memory can contain tokens, cookies, or other secrets that enable follow-on attacks.

Do this: Update every Chromium-based browser in your fleet to a patched version now and verify enforcement through browser management policy.

AI-generated from public data, 2026-07-21. Verify against the vendor advisory before acting.

Senserva AI Opinion and rich prompt for CVE-2021-37976

Copy this prompt into Claude, ChatGPT, or Copilot. The facts are included, sourced from this page.

Patch now
Exploited in the wild: confirmed by the CISA KEV catalog, not predicted.
The fix ships from the vendor: Chrome Releases (security updates).
Do this now: Federal remediation deadline 2021-11-17; treat it as your outer bound. Patch now and verify deployment on every exposed device.

Updated August 14, 2026. Data refreshed on every build from MSRC, CISA KEV, and FIRST EPSS.

Full tracking and change history for CVE-2021-37976

Published
2021-11-03
Last revised
2021-11-03
Changes tracked
1

Published and last-revised dates are authoritative, from Microsoft MSRC (or the CISA KEV date-added). Senserva additionally records day-to-day changes from 2026-07-07, refreshed several times a day; the change count reflects that forward-only tracking.

Senserva Watchevery change we have recorded for this one
What changed, and when
  • 2021-11-03 added to the CISA KEV catalog by CISA
  • 2026-07-17 CVSS 0.0 to 6.5; EPSS first scored at 19.9%
  • 2026-08-13 EPSS 19.9% to 19.8%

Recorded by Senserva on the dates shown, from CISA KEV and FIRST EPSS. This is what moved and when, which neither the vendor advisory nor NVD publishes.

CISA required action

Federal (BOD 22-01) remediation due date: 2021-11-17 (past due).

Apply updates per vendor instructions.

Official fix for CVE-2021-37976

The authoritative fix and affected-version list are published by the vendor. Find the Chromium advisory on Chrome Releases (security updates).

Common questions about CVE-2021-37976

Is CVE-2021-37976 actively exploited?

Yes. CVE-2021-37976 was added to the CISA Known Exploited Vulnerabilities (KEV) catalog on 2021-11-03, which means exploitation in the wild has been confirmed, not predicted. Its EPSS 30-day exploitation probability is 20%.

What is the CISA deadline and required action for CVE-2021-37976?

CISA set the federal (BOD 22-01) remediation due date at 2021-11-17, which has passed; treat any unremediated system as overdue. The verbatim required action: Apply updates per vendor instructions.

What fixes CVE-2021-37976?

The authoritative fix is in the vendor advisory: see Chrome Releases (security updates) for the patched Chromium versions and any workarounds. KEV listing makes this a fix-first item: patch it ahead of higher-CVSS issues nobody is exploiting.

Can I ask my own AI about CVE-2021-37976?

Yes. This page includes a free, ready-to-paste AI prompt containing CVE-2021-37976's key facts: severity, CVSS, EPSS, the KEV date, the CISA due date, and the required action. Copy it into Claude, ChatGPT, or Copilot; the data is refreshed twice a day (5 AM and 3 PM US Central).

Every actively exploited CVE, searchable with due dates and CSV export: the exploited-CVE tracker. The newest additions: exploited this week.

New to a term on this page? CVE, KB, KEV, CVSS, and EPSS are each explained once, on the Senserva security lexicon. Reference: Microsoft CVE and vulnerability management and the Microsoft patching guide.
Provided as is, without warranty; verify against the vendor advisory before acting. Data notice and terms.