CVE-2020-8187
Status: ModifiedHigh (7.5)—
Improper input validation in Citrix ADC and Citrix Gateway versions before 11.1-63.9 and 12.0-62.10 allows unauthenticated users to perform a denial of service attack.
CVSS
- Version: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Base score: 7.5
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 1.95%
- Percentile among all scored CVEs: 79
- Score date: 10/1/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
Affected technologies (2)
CWEs
- CWE-20
- CWE-20
References
Raw JSON (NVD)
Show
{
"id": "CVE-2020-8187",
"cveTags": [],
"metrics": {
"cvssMetricV2": [
{
"type": "Primary",
"source": "nvd@nist.gov",
"cvssData": {
"version": "2.0",
"baseScore": 5,
"accessVector": "NETWORK",
"vectorString": "AV:N/AC:L/Au:N/C:N/I:N/A:P",
"authentication": "NONE",
"integrityImpact": "NONE",
"accessComplexity": "LOW",
"availabilityImpact": "PARTIAL",
"confidentialityImpact": "NONE"
},
"acInsufInfo": false,
"impactScore": 2.9,
"baseSeverity": "MEDIUM",
"obtainAllPrivilege": false,
"exploitabilityScore": 10,
"obtainUserPrivilege": false,
"obtainOtherPrivilege": false,
"userInteractionRequired": false
}
],
"cvssMetricV31": [
{
"type": "Primary",
"source": "nvd@nist.gov",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 7.5,
"attackVector": "NETWORK",
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
"integrityImpact": "NONE",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "HIGH",
"privilegesRequired": "NONE",
"confidentialityImpact": "NONE"
},
"impactScore": 3.6,
"exploitabilityScore": 3.9
}
]
},
"affected": [
{
"source": "support@hackerone.com",
"affectedData": [
{
"vendor": "n/a",
"product": "Citrix ADC, Citrix Gateway",
"versions": [
{
"status": "affected",
"version": "11.1-63.9, 12.0-62.10"
}
]
}
]
}
],
"published": "2020-07-10T16:15:11.937",
"references": [
{
"url": "https://support.citrix.com/article/CTX276688",
"tags": [
"Vendor Advisory"
],
"source": "support@hackerone.com"
},
{
"url": "https://support.citrix.com/article/CTX276688",
"tags": [
"Vendor Advisory"
],
"source": "af854a3a-2127-422b-91ae-364da2661108"
}
],
"vulnStatus": "Modified",
"weaknesses": [
{
"type": "Secondary",
"source": "support@hackerone.com",
"description": [
{
"lang": "en",
"value": "CWE-20"
}
]
},
{
"type": "Primary",
"source": "nvd@nist.gov",
"description": [
{
"lang": "en",
"value": "CWE-20"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "Improper input validation in Citrix ADC and Citrix Gateway versions before 11.1-63.9 and 12.0-62.10 allows unauthenticated users to perform a denial of service attack."
},
{
"lang": "es",
"value": "Una comprobación de entrada inapropiada en Citrix ADC y Citrix Gateway versiones anteriores a 11.1-63.9 y 12.0-62.10, permite a usuarios no autenticados llevar a cabo un ataque de denegación de servicio"
}
],
"lastModified": "2026-06-17T03:26:00.920",
"configurations": [
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:o:citrix:application_delivery_controller_firmware:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "906C3ABF-27C3-4ADD-9350-BDAA82994C34",
"versionEndExcluding": "11.1-63.9",
"versionStartIncluding": "11.1"
},
{
"criteria": "cpe:2.3:o:citrix:application_delivery_controller_firmware:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "85149DE8-82B5-4105-BBA5-F69B45AB4411",
"versionEndExcluding": "12.0-62.10",
"versionStartIncluding": "12.0"
}
],
"operator": "OR"
},
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:h:citrix:application_delivery_controller:-:*:*:*:*:*:*:*",
"vulnerable": false,
"matchCriteriaId": "80E69E10-6F40-4FE4-9D84-F6C25EAB79D8"
}
],
"operator": "OR"
}
],
"operator": "AND"
},
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:o:citrix:netscaler_gateway_firmware:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "36CA9337-8219-4BAE-A050-5A56C3E60E32",
"versionEndExcluding": "11.1-63.9",
"versionStartIncluding": "11.1"
},
{
"criteria": "cpe:2.3:o:citrix:netscaler_gateway_firmware:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "01DB94F6-D733-4A4E-9353-68D59C5CB5DC",
"versionEndExcluding": "12.0-62.10",
"versionStartIncluding": "12.0"
}
],
"operator": "OR"
},
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:h:citrix:netscaler_gateway:-:*:*:*:*:*:*:*",
"vulnerable": false,
"matchCriteriaId": "DEBB9B6A-1CAD-4D82-9B1E-939921986053"
}
],
"operator": "OR"
}
],
"operator": "AND"
}
],
"sourceIdentifier": "support@hackerone.com"
}