Actively exploited in the wild
Checkbox Survey Deserialization of Untrusted Data Vulnerability
Checkbox - Checkbox Survey · Listed in the CISA KEV since 2022-04-11. This indicates confirmed attacks in production environments.
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.
CVE-2021-27852
CriticalCVSS 9.8KEVSummary
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.
Risk Assessment
A remote attacker can execute arbitrary code on the Checkbox Survey server, potentially leading to full system compromise and breach of survey data.
Recommendation
Update Checkbox Survey to version 7 or later that includes a fix.
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Original NVD description (English source)
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.