Checkbox · Checkbox Survey

CVE-2021-27852

Checkbox Survey Deserialization of Untrusted Data Vulnerability

Evidence

Source & freshness

Full source status →

CISA KEV catalog Core KEV record

CVE, vendor/product, CISA dates, ransomware status, description, required action, and notes.

Catalog 2026.07.24 · Retrieved 2026-07-25 20:49 UTC Open official CISA feed ↗

MITRE CWE catalog CWE context

CWE names and plain-language weakness descriptions. CISA supplies the CWE assignment itself.

Retrieved 2026-07-25 20:59 UTC Open official MITRE CWE catalog ↗

National Vulnerability Database NVD technical context

CVSS metrics, NVD timeline, and related NVD record data are stored locally.

Retrieved Jul 25, 2026, 08:49 PM UTC Open NVD record ↗

CISA KEV record

CISA date added: 2022-04-11
CISA due date: 2022-05-02
Known ransomware use: Unknown

NVD risk context

9.8 CRITICAL

CVSS is a technical severity score. CISA’s KEV status remains the evidence that this vulnerability is known to be exploited.

View NVD record ↗

Attack vector

Network

The vulnerable service can be reached remotely over a network.

Attack complexity

Low

Exploitation does not require unusual conditions beyond normal attacker control.

Privileges required

None

The attacker does not need an existing account or privileges.

User interaction

None

No action by another user is required.

Description

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

Required action

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.

NVD reference index

Vendor and remediation references

NVD has not tagged a reference for this KEV as a patch, mitigation, release note, or vendor advisory.

Other NVD references (2)

https://www.kb.cert.org/vuls/id/706695 ↗
Third Party AdvisoryUS Government Resource NVD reference source: cret@cert.org
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-27852 ↗
US Government Resource NVD reference source: 134c704f-9b21-4f2e-91b3-4a467353bcc0

MITRE CWE context

CWE classification

CWE-502 Deserialization of Untrusted Data

The product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.

View official MITRE CWE details ↗

NVD record timing

NVD record timeline

These dates describe NVD’s record, not CISA’s KEV addition or remediation due date.

NVD published: May 27, 2021, 09:15 PM UTC
NVD last updated: Jun 17, 2026, 03:45 AM UTC

Advanced: view the technical CVSS vector

This standardized code is intended for security tools and technical analysts. The plain-language risk summary above explains its main points.

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

View NVD record ↗

CISA notes

https://nvd.nist.gov/vuln/detail/CVE-2021-27852

https://nvd.nist.gov/vuln/detail/CVE-2021-27852