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CVE-2021-27852

Checkbox Survey Deserialization of Untrusted Data

9.8 CRITICALActively exploited (CISA KEV)EPSS 30.3%
  1. Published27 May 2021
  2. Added to CISA KEV11 Apr 2022
  3. Remediation due2 May 2022
Actively exploited (CISA KEV)

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

Added to KEV: 11 Apr 2022Federal remediation due: 2 May 2022

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.

CVSS 3.1 breakdown

Attack vectorNetwork
Attack complexityLow
Privileges requiredNone
User interactionNone
ScopeUnchanged
ConfidentialityHigh
IntegrityHigh
AvailabilityHigh
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected products

Checkbox Survey< 7.0

Remediation

Fixed in
Checkbox Survey≥ 7.0

References

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Frequently asked

Is CVE-2021-27852 being actively exploited?

Yes. CVE-2021-27852 is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, added 11 Apr 2022.

How severe is CVE-2021-27852?

CVE-2021-27852 has a CVSS 3.1 base score of 9.8, rated critical. EPSS estimates a 30.3% probability of exploitation.

Which products are affected by CVE-2021-27852?

Affected products include Checkbox Survey.

How do I fix CVE-2021-27852?

Upgrade affected software to a fixed version, for example Checkbox Survey 7.0 or later, then confirm no affected versions remain in your inventory.

How Secuno handles this

Secuno correlates vulnerabilities like CVE-2021-27852 against the real software inventory on every managed device, every day. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. Because it is on the CISA KEV list, Secuno flags any affected asset as top-priority automatically. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.

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Data from the NVD, CISA KEV catalog and FIRST EPSS. CVSS 3.1 base score shown where available.