CISA KEV · Known exploitedHigh

CVE-2021-21220

Google Chromium V8

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
8.8
EPSS
69.3%
99.3% percentile
CISA KEV
Listed
Published
2021.04.27
PRIORITY ASSESSMENT

Immediate review

CISA has listed this vulnerability in the Known Exploited Vulnerabilities catalog.

Known exploitationConfirmed by CISA KEV
Exploit probability69.3%
Technical severityCVSS 8.8

Vulnerability overview

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.

Affected product and versions

Product
Google Chromium V8
Affected versions
unspecified, < 89.0.4389.128, 32, 33, 34
Fixed versions
89.0.4389.128

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide
CISA required action

Apply updates per vendor instructions.

Due date: 2021.11.17
  1. 1
    Identify

    Confirm that Google Chromium V8 and an affected version are present.

  2. 2
    Prioritize

    Combine exploitation signals with asset exposure and business criticality.

  3. 3
    Remediate

    Follow the vendor advisory or supported update path and preserve rollback options.

  4. 4
    Verify

    Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
CWE
CWE-122, CWE-20, CWE-787
KEV added
2021.11.03
Ransomware use
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