CVE-2021-37999Network attack vector

Script injection via insufficient New Tab validation

Published Nov 23, 2021 · Updated Aug 4, 2024

Cross-site scripting in Google Chrome before 95.0.4638.69 allows remote attackers to inject scripts or HTML via a crafted page. Google identifies insufficient data validation in the New Tab Page but has not disclosed the affected code path or the exact input validation failure. A user must open attacker-controlled HTML; exploitation alters content in a new browser tab, with no reported availability impact.

CVSS severity6.1
Medium
EPSS probability0.95%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Cross-site scripting in Google Chrome before 95.0.4638.69 allows remote attackers to inject scripts or HTML via a crafted page. Google identifies insufficient data validation in the New Tab Page but has not disclosed the affected code path or the exact input validation failure. A user must open attacker-controlled HTML; exploitation alters content in a new browser tab, with no reported availability impact.

The record

CVE
CVE-2021-37999
Published
Nov 23, 2021
Updated
Aug 4, 2024
Vendor
Google Cloud
Product
Google Chrome
Classifications
CWE-79
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Nov 23, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=unspecified <95.0.4638.69

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Google Cloud · Google Chromeversion=unspecified <95.0.4638.69

Published CVSS scores

4.3NIST NVDAV:N/AC:M/Au:N/C:N/I:P/A:N
6.1NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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