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CVE-2021-21220

Google Chromium V8 Improper Input Validation

8.8 HIGHActively exploited (CISA KEV)Public exploitEPSS 70.4%
  1. Published26 Apr 2021
  2. Added to CISA KEV3 Nov 2021
  3. Remediation due17 Nov 2021
Actively exploited (CISA KEV)

Google Chromium V8 Engine contains an improper input validation 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

Insufficient validation of untrusted input in V8 in Google Chrome prior to 89.0.4389.128 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< 89.0.4389.128
Fedoraproject Fedora32 · 33 · 34

Remediation

Fixed in
Google Chrome≥ 89.0.4389.128

References

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Frequently asked

Is CVE-2021-21220 being actively exploited?

Yes. CVE-2021-21220 is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, added 3 Nov 2021.

How severe is CVE-2021-21220?

CVE-2021-21220 has a CVSS 3.1 base score of 8.8, rated high. EPSS estimates a 70.4% probability of exploitation.

Which products are affected by CVE-2021-21220?

Affected products include Google Chrome, Fedoraproject Fedora.

How do I fix CVE-2021-21220?

Upgrade affected software to a fixed version, for example Google Chrome 89.0.4389.128 or later, then confirm no affected versions remain in your inventory.

How Secuno handles this

Secuno correlates vulnerabilities like CVE-2021-21220 against the real software inventory on every managed device, every day. 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, Secuno flags any affected asset as top-priority automatically. 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.