CVE-2021-23446Public exploitNetwork attack vector

Application hang via numeric-validation regex backtracking

Published Sep 29, 2021 · Updated Sep 16, 2024

Regular expression denial of service in Handsoncode Handsontable before 10.0.0 allows remote attackers to interrupt host applications. The Handsontable.helper.isNumeric numeric-value check applies an inefficient regular expression that backtracks heavily on long whitespace-only strings. A host application must pass attacker-controlled cell data to the helper; processing can consume the JavaScript thread for several seconds and stall the application.

CVSS severity7.5
High
EPSS probability2.96%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Regular expression denial of service in Handsoncode Handsontable before 10.0.0 allows remote attackers to interrupt host applications. The Handsontable.helper.isNumeric numeric-value check applies an inefficient regular expression that backtracks heavily on long whitespace-only strings. A host application must pass attacker-controlled cell data to the helper; processing can consume the JavaScript thread for several seconds and stall the application.

The record

CVE
CVE-2021-23446
Published
Sep 29, 2021
Updated
Sep 16, 2024
Vendor
Handsoncode
Product
Handsontable
Classifications
CWE-1333, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 29, 2021CVE publishedPublication date reported by the CVE source.
  2. Sep 16, 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=0 <unspecified
  2. Affected versionversion=unspecified <10.0.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Handsoncode · Handsontableversion=0 <unspecified; version=unspecified <10.0.0

Published CVSS scores

5.0NIST NVDAV:N/AC:L/Au:N/C:N/I:N/A:P
7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
7.5SnykCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

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 exploitPublished

Weakness, pattern, technique

CWE-1333Inefficient Regular Expression Complexity
T1499.004Application or System Exploitation

Public exploit references

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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