CVE-2021-27852

published 2021-05-27

CVE-2021-27852: Deserialization of Untrusted Data vulnerability in CheckboxWeb.dll of Checkbox Survey allows an unauthenticated remote attacker to execute arbitrary code. This…

Priority P1 93 critical 9.8 CVSS 3.1

AV N AC L PR N UI N S U C H I H A H

KEV ITW

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.

Affected

2 ranges

Vendor	Product	Version range	Fixed in
checkbox	survey	< 7.0	7.0
checkbox	survey	>= unspecified < 7	7

Detection & IOCs extracted from sources · hover to see the quote

filename CheckboxWeb.dll↗

• → Monitor for unauthenticated deserialization requests targeting CheckboxWeb.dll in Checkbox Survey deployments running versions prior to 7. ↗
• → Checkbox Survey versions 6 and earlier are end-of-life; presence of these versions on a network is itself an indicator of risk and should be flagged for immediate removal. ↗

• · The vulnerability is specifically within CheckboxWeb.dll; exploitation does not require authentication, meaning perimeter authentication controls alone are insufficient as a mitigation. ↗

CVSS provenance

nvd v3.1 9.8 CRITICAL CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

nvd v2.0 7.5 HIGH AV:N/AC:L/Au:N/C:P/I:P/A:P

vulncheck 9.8 CRITICAL

cisa 9.8 CRITICAL

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