CVE-2021-27852

Published: May 27, 2021Updated: Oct 24, 2025 Sources: CVE List NVD BDUCWE-502

9.8CRITICAL

NVD MITRE

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.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

AC:LAttack Complexity

Low

PR:NPrivileges Required

None

UI:NUser Interaction

None

Scope

S:UScope

Unchanged

Impact

C:HConfidentiality

High

I:HIntegrity

High

A:HAvailability

High

Open in CVSS calculator →

Weaknesses

CWE-502

Affected Products

Checkbox Technology, Inc.

commercial

Checkbox SurveySaaS

Web & CMS Plugins / site-builder

Checkbox

SurveySaaS

Web & CMS Plugins / site-builder

and 1 more affected products View all →

Exploitability

CISA Known Exploited Vulnerability

Added to KEV:Apr 11, 2022

Remediation due:May 2, 2022

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.

Official Patch Available

Is your org exposed to CVE-2021-27852?Request an assessment to establish which checks are appropriate for your systems. Check my exposure

Attack Graph

Products CVE Techniques Tactics

Click technique nodes for MITRE ATT&CK details · drag to pan · Ctrl/⌘ + scroll to zoom, or go fullscreen.

MITRE ATT&CK

3 techniques

Execution

Initial Access

View detailed technique mapping

References

https://www.kb.cert.org/vuls/id/706695

kb.cert.org

https://vuldb.com/ru/?id.176004

vuldb.com

https://www.cisa.gov/sites/default/files/csv/known_exploited_vulnerabilities.csv

cisa.gov

and 2 more references View all →

Unlock Complete Vulnerability Intelligence

Get the full picture for CVE-2021-27852 and every CVE in our database. Create a free account — no credit card required.

Create Free Account

Plain-language analysis

Impact assessment and exploitation scenario in plain English

Attack graph visualization

Interactive attack path and kill chain mapping

Exploit details & PoC links

ExploitDB, Metasploit, GitHub PoCs with direct links

Nuclei scanner templates

Ready-to-use vulnerability scanner templates

Full remediation guide

Patch instructions, workarounds, and compliance impact

Interactive AI chat

Ask questions about this vulnerability in natural language

Related vulnerabilities

Semantically similar CVEs and attack patterns

REST API & MCP access

Integrate vulnerability data into your workflows