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Exploited End of life

CVE-2021-27852

Checkbox Survey · ERP, business applications and databases

Checkbox Survey Deserialization of Untrusted Data Vulnerability

At a glance

Exploited. Added to CISA’s catalog of exploited vulnerabilities on April 11, 2022.

End-of-life product: no patch is coming. Remove it or isolate it from the network.

Affected product: Checkbox Survey (category ERP, business applications and databases, indicative classification). Name in CISA’s catalog: Checkbox Checkbox Survey.

What should I do?

This product has reached end of life: no patch is coming. Remove it or isolate it from the network.

Deadline set by CISA for US federal agencies: 21 days (due May 2, 2022). It only binds those agencies, but it is a useful measure of urgency.

Original text of the required action (CISA)

Versions 6 and earlier for this product are end-of-life and must be removed from agency networks. Versions 7 and later are not considered vulnerable.

Timeline

  1. Vulnerability published Publication date (NVD)
  2. Exploitation confirmed Added to CISA’s KEV catalog
  3. CISA deadline Remediation deadline set for US federal agencies

The facts, with their sources

Exploitation confirmed
Yes, on April 11, 2022 Date added to the catalog of exploited vulnerabilities. Exploitation itself may have started earlier. Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
Ransomware
No known use to date That does not guarantee it is not being used: the information is not public. Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
Hunt for compromise
Not requested by CISA Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
CISA required action
This product has reached end of life: no patch is coming. Remove it or isolate it from the network. Rewritten by this site from CISA’s original text. Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
CISA deadline
May 2, 2022, 21 days Set for US federal agencies: a measure of urgency, not an obligation elsewhere. Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
Vulnerability published
May 27, 2021 Source: National Vulnerability Database (NVD), collected September 29, 2026 at 15:00 UTC
Product according to CISA
Checkbox Checkbox Survey Filed by this site under “ERP, business applications and databases” (indicative classification). Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Technical detail of the score: attack vector, complexity, impact. Source: National Vulnerability Database (NVD), collected September 29, 2026 at 15:00 UTC

Severity and activity

9.8 / 10 CVSS severity: critical

Score from the NVD. Collected Sep 29, 2026.

— Probability of exploitation in the next 30 days (EPSS)

FIRST’s EPSS model. Since exploitation is already confirmed, this figure is mostly useful to compare activity. Collected Sep 29, 2026.

Description

Deserialization of Untrusted Data vulnerability in CheckboxWeb.dll of Checkbox Survey allows an unauthenticated remote attacker to execute arbitrary code. This issue affects: Checkbox Survey versions prior to 7.

Official description from the NVD, collected Sep 29, 2026. CVE® description © The MITRE Corporation.

Deserialization of Untrusted Data vulnerability in CheckboxWeb.dll of Checkbox Survey allows an unauthenticated remote attacker to execute arbitrary code.

Summary from CISA (KEV catalog).

CERT-FR advisories

No advisory among the latest CERT-FR publications this site follows. That does not mean there are none.

Information reused under the Open Licence 2.0 (Etalab); the date of last update is shown for each advisory. This site is neither affiliated with nor endorsed by ANSSI.

Sources for this page

  • CISA KEV catalog: exploitation, date added, required action, deadline, ransomware.
  • NVD (NIST): CVSS severity, publication date, description, vendor references.
  • EPSS (FIRST): probability of exploitation.
  • CERT-FR: advisories and alerts (in French).
  • Brand and category: indicative classification by this site (method).