CVE-2021-33605Network attack vector

Unauthorized value changes via incomplete disabled-item validation

Published Aug 25, 2021 · Updated Sep 17, 2024

Improper validation in Vaadin 12 through 20 CheckboxGroup allows remote authenticated users to change disabled Checkbox values. CheckboxGroup value-change validation fails to compare old and new selections for items disabled by ItemEnabledProvider, so a crafted client update can alter them. The application must expose an enabled group containing a server-disabled checkbox; the flaw changes application state without disclosing data or interrupting service.

CVSS severity4.3
Medium
EPSS probability0.66%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper validation in Vaadin 12 through 20 CheckboxGroup allows remote authenticated users to change disabled Checkbox values. CheckboxGroup value-change validation fails to compare old and new selections for items disabled by ItemEnabledProvider, so a crafted client update can alter them. The application must expose an enabled group containing a server-disabled checkbox; the flaw changes application state without disclosing data or interrupting service.

The record

CVE
CVE-2021-33605
Published
Aug 25, 2021
Updated
Sep 17, 2024
Vendor
Vaadin
Product
Vaadin Checkbox Flow
Classifications
CWE-754, T1565.002
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 25, 2021CVE publishedPublication date reported by the CVE source.
  2. Sep 17, 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=1.2.0 <unspecified
  2. Affected versionversion=14.5.0 <unspecified
  3. Affected versionversion=18.0.0 <unspecified
  4. Affected versionversion=2.0.0 <unspecified
  5. Affected versionversion=3.0.0 <unspecified
  6. Affected versionversion=unspecified <=14.6.7
  7. Affected versionversion=unspecified <2.0.0
  8. Affected versionversion=unspecified <=20.0.5
  9. Affected versionversion=unspecified <3.0.0
  10. Affected versionversion=unspecified <=4.0.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Vaadin · Vaadin Checkbox Flowversion=1.2.0 <unspecified; version=14.5.0 <unspecified; version=18.0.0 <unspecified; version=2.0.0 <unspecified; version=3.0.0 <unspecified; version=unspecified <=14.6.7; version=unspecified <2.0.0; version=unspecified <=20.0.5; version=unspecified <3.0.0; version=unspecified <=4.0.1
Vaadin · Vaadin Frameworkversion=12.0.0 <unspecified; version=14.0.0 <unspecified; version=14.5.0 <unspecified; version=15.0.0 <unspecified; version=18.0.0 <unspecified; version=unspecified <14.0.0; version=unspecified <14.5.0; version=unspecified <=14.6.7; version=unspecified <=17.0.11; version=unspecified <=20.0.5

Published CVSS scores

4.3Vaadin Ltd.CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
4.0NIST NVDAV:N/AC:L/Au:S/C:N/I:P/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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-754Improper Check for Unusual or Exceptional Conditions
T1565.002Transmitted Data Manipulation

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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