Exploitation evidence
Known exploited · CISA KEV listed
Added 2022-04-11. Ransomware campaign use: Unknown.
CISA 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.
CISA due date: 2022-05-02. This is the catalog’s deadline, not an assessment of your organization’s exposure.
KEV checked 13 Nov 2026, 00:20 Jerusalem · Original catalog ↗Reported products and versions
Checkbox / Survey
Default status: Not specified
- affected: unspecified to < 7 (custom)
Fixes and workarounds
No explicit solution text in the downloaded CVE record. Consult the vendor advisory; unaffected version ranges are shown above as reported, not inferred as a patch recommendation.
Sources and related reporting
Observed change timeline
History begins when Egret first downloads each source. It is not the complete upstream CVE history.
12 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-12",
"epss": 0.30258,
"percentile": 0.9825
}10 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-10",
"epss": 0.30258,
"percentile": 0.98238
}09 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-09",
"epss": 0.30258,
"percentile": 0.98236
}08 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-08",
"epss": 0.30258,
"percentile": 0.98235
}07 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-07",
"epss": 0.30258,
"percentile": 0.98234
}06 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-06",
"epss": 0.30258,
"percentile": 0.98232
}06 Nov 2026, 06:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-05",
"epss": 0.30258,
"percentile": 0.9823
}05 Nov 2026, 18:20 Jerusalem · CVE Program record changed
Stored CNA snapshot at this observation.
{
"containers": {
"adp": [
{
"providerMetadata": {
"dateUpdated": "2024-08-03T21:33:16.318Z",
"orgId": "af854a3a-2127-422b-91ae-364da2661108",
"shortName": "CVE"
},
"references": [
{
"tags": [
"x_transferred"
],
"url": "https://www.kb.cert.org/vuls/id/706695"
}
],
"title": "CVE Program Container"
},
{
"metrics": [
{
"other": {
"content": {
"id": "CVE-2021-27852",
"options": [
{
"Exploitation": "active"
},
{
"Automatable": "yes"
},
{
"Technical Impact": "total"
}
],
"role": "CISA Coordinator",
"timestamp": "2025-02-06T19:47:57.660138Z",
"version": "2.0.3"
},
"type": "ssvc"
}
},
{
"other": {
"content": {
"dateAdded": "2022-04-11",
"reference": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-27852"
},
"type": "kev"
}
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-502",
"description": "CWE-502 Deserialization of Untrusted Data",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2025-10-21T23:25:44.136Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"references": [
{
"tags": [
"government-resource"
],
"url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-27852"
}
],
"timeline": [
{
"lang": "en",
"time": "2022-04-11T00:00:00.000Z",
"value": "CVE-2021-27852 added to CISA KEV"
}
],
"title": "CISA ADP Vulnrichment"
}
],
"cna": {
"affected": [
{
"product": "Survey",
"vendor": "Checkbox",
"versions": [
{
"lessThan": "7",
"status": "affected",
"version": "unspecified",
"versionType": "custom"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "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."
}
],
"metrics": [
{
"cvssV3_1": {
"attackComplexity": "LOW",
"attackVector": "NETWORK",
"availabilityImpact": "HIGH",
"baseScore": 9.8,
"baseSeverity": "CRITICAL",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"privilegesRequired": "NONE",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"version": "3.1"
}
}
],
"providerMetadata": {
"dateUpdated": "2023-10-13T14:59:08.148Z",
"orgId": "37e5125f-f79b-445b-8fad-9564f167944b",
"shortName": "certcc"
},
"references": [
{
"url": "https://www.kb.cert.org/vuls/id/706695"
}
],
"source": {
"discovery": "UNKNOWN"
},
"x_generator": {
"engine": "cveClient/1.0.15"
},
"x_legacyV4Record": {
"CVE_data_meta": {
"ASSIGNER": "cert@cert.org",
"ID": "CVE-2021-27852",
"STATE": "PUBLIC"
},
"affects": {
"vendor": {
"vendor_data": [
{
"product": {
"product_data": [
{
"product_name": "Survey",
"version": {
"version_data": [
{
"version_affected": "<",
"version_value": "7"
}
]
}
}
]
},
"vendor_name": "Checkbox"
}
]
}
},
"data_format": "MITRE",
"data_type": "CVE",
"data_version": "4.0",
"description": {
"description_data": [
{
"lang": "eng",
"value": "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."
}
]
},
"generator": {
"engine": "Vulnogram 0.0.9"
},
"impact": {
"cvss": {
"attackComplexity": "LOW",
"attackVector": "NETWORK",
"availabilityImpact": "HIGH",
"baseScore": 9.8,
"baseSeverity": "CRITICAL",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"privilegesRequired": "NONE",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"version": "3.1"
}
},
"references": {
"reference_data": [
{
"name": "https://www.kb.cert.org/vuls/id/706695",
"refsource": "MISC",
"url": "https://www.kb.cert.org/vuls/id/706695"
}
]
},
"source": {
"discovery": "UNKNOWN"
}
}
}
},
"cveMetadata": {
"assignerOrgId": "37e5125f-f79b-445b-8fad-9564f167944b",
"assignerShortName": "certcc",
"cveId": "CVE-2021-27852",
"datePublished": "2021-05-27T20:55:11.000Z",
"dateReserved": "2021-03-01T00:00:00.000Z",
"dateUpdated": "2025-10-21T23:25:44.136Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.1"
}04 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-04",
"epss": 0.30258,
"percentile": 0.98229
}03 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-03",
"epss": 0.30258,
"percentile": 0.98226
}03 Nov 2026, 02:22 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-02",
"epss": 0.30258,
"percentile": 0.98223
}03 Nov 2026, 02:22 Jerusalem · CISA KEV status changed
Stored KEV snapshot at this observation.
{
"cveID": "CVE-2021-27852",
"cwes": [
"CWE-502"
],
"dateAdded": "2022-04-11",
"dueDate": "2022-05-02",
"forensicTriage": "No",
"knownRansomwareCampaignUse": "Unknown",
"notes": "https://nvd.nist.gov/vuln/detail/CVE-2021-27852",
"product": "Checkbox Survey",
"requiredAction": "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.",
"shortDescription": "Deserialization of Untrusted Data vulnerability in CheckboxWeb.dll of Checkbox Survey allows an unauthenticated remote attacker to execute arbitrary code.",
"vendorProject": "Checkbox",
"vulnerabilityName": "Checkbox Survey Deserialization of Untrusted Data Vulnerability"
}