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CVE-2021-21166

Google Chromium Race Condition

8.8 HIGHActively exploited (CISA KEV)EPSS 24.0%
  1. Published9 Mar 2021
  2. Added to CISA KEV3 Nov 2021
  3. Remediation due17 Nov 2021
Actively exploited (CISA KEV)

Google Chromium contains a race condition vulnerability that allows a remote attacker to potentially exploit heap corruption 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.

Added to KEV: 3 Nov 2021Federal remediation due: 17 Nov 2021

Description

Data race in audio in Google Chrome prior to 89.0.4389.72 allowed a remote attacker to potentially exploit heap corruption via a crafted HTML page.

CVSS 3.1 breakdown

Attack vectorNetwork
Attack complexityLow
Privileges requiredNone
User interactionRequired
ScopeUnchanged
ConfidentialityHigh
IntegrityHigh
AvailabilityHigh
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Affected products

Google Chrome< 89.0.4389.72
Debian Linux10.0
Fedoraproject Fedora32 · 33 · 34

Remediation

Fixed in
Google Chrome≥ 89.0.4389.72

References

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Frequently asked

Is CVE-2021-21166 being actively exploited?

Yes. CVE-2021-21166 is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, added 3 Nov 2021.

How severe is CVE-2021-21166?

CVE-2021-21166 has a CVSS 3.1 base score of 8.8, rated high. EPSS estimates a 24.0% probability of exploitation.

Which products are affected by CVE-2021-21166?

Affected products include Google Chrome, Debian Linux, Fedoraproject Fedora.

How do I fix CVE-2021-21166?

Upgrade affected software to a fixed version, for example Google Chrome 89.0.4389.72 or later, then confirm no affected versions remain in your inventory.

How Secuno handles this

Secuno correlates vulnerabilities like CVE-2021-21166 against the real software inventory on every managed device, as each hourly inventory arrives. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. Because it is on the CISA KEV list, a risk for it never ranks below high, and the update that fixes it moves to the Emergency patch lane. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.

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Data from the NVD, CISA KEV catalog and FIRST EPSS. CVSS 3.1 base score shown where available.