CVE-2021-33609Network attack vector

Authenticated heap exhaustion via excessive row requests

Published Oct 13, 2021 · Updated Sep 16, 2024

Denial of service in Vaadin Framework and Vaadin Server 8.0.0 through 8.14.0 allows remote authenticated users to interrupt service via excessive row requests. The DataCommunicator class used by ComboBox and Grid accepts an arbitrary requested row count without a limiting check, causing large back-end datasets to consume heap. Access requires authentication and a view containing an affected component; the advisory reports availability impact without code execution or data disclosure.

CVSS severity4.3
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

Denial of service in Vaadin Framework and Vaadin Server 8.0.0 through 8.14.0 allows remote authenticated users to interrupt service via excessive row requests. The DataCommunicator class used by ComboBox and Grid accepts an arbitrary requested row count without a limiting check, causing large back-end datasets to consume heap. Access requires authentication and a view containing an affected component; the advisory reports availability impact without code execution or data disclosure.

The record

CVE
CVE-2021-33609
Published
Oct 13, 2021
Updated
Sep 16, 2024
Vendor
Vaadin
Product
Vaadin Framework
Classifications
CWE-20, CWE-400, T1496
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Oct 13, 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=8.0.0 <unspecified
  2. Affected versionversion=unspecified <=8.14.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Vaadin · Vaadin Frameworkversion=8.0.0 <unspecified; version=unspecified <=8.14.0
Vaadin · Vaadin Serverversion=8.0.0 <unspecified; version=unspecified <=8.14.0

Published CVSS scores

4.0NVDAV:N/AC:L/Au:S/C:N/I:N/A:P
4.3Vaadin Ltd.CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L

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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-20Improper Input Validation
CWE-400Uncontrolled Resource Consumption
T1496Resource Hijacking

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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