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CVE-2021-27852: Checkbox Survey Deserialization of Untrusted Data Vulnerability
Checkbox Checkbox Survey · in CISA KEV since 2022-04-11
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2022-04-11added to KEV
2022-05-02federal remediation due date
30.26%EPSS exploit probability (30 days) 98.2th percentile
9.8 CRITICALCVSS 3.1
Unknownknown ransomware use
319days from NVD publication to KEV
What it is
Deserialization of Untrusted Data vulnerability in CheckboxWeb.dll of Checkbox Survey allows an unauthenticated remote attacker to execute arbitrary code.
Required action (CISA)
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.
| CWE | CWE-502 |
|---|---|
| CVSS vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVD published | 2021-05-27 (Analyzed) |
Original records: NVD · CISA KEV · JSON: /api/cve/CVE-2021-27852.json · all KEV CVEs
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Get the full file: Exploited Vulnerabilities Brief – September 2026 ($29): this month's KEV additions ranked by EPSS, ransomware use and due date, ready to hand to a patch team. Checkout by Polar.
Get the full file: Exploited Vulnerabilities Brief – September 2026 ($29): this month's KEV additions ranked by EPSS, ransomware use and due date, ready to hand to a patch team. Checkout by Polar.