Vulnerability-Lookup

FKIE_CVE-2021-22955

Vulnerability from fkie_nvd - Published: 2021-12-07 14:15 - Updated: 2026-06-17 03:38

Severity

7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Summary

A unauthenticated denial of service vulnerability exists in Citrix ADC <13.0-83.27, <12.1-63.22 and 11.1-65.23 when configured as a VPN (Gateway) or AAA virtual server could allow an attacker to cause a temporary disruption of the Management GUI, Nitro API, and RPC communication.

References

	URL	Tags
	support@hackerone.com	https://support.citrix.com/article/CTX330728	Vendor Advisory
	af854a3a-2127-422b-91ae-364da2661108	https://support.citrix.com/article/CTX330728	Vendor Advisory

Impacted products

Vendor	Product	Version
citrix	application_delivery_controller_firmware	*
citrix	application_delivery_controller_firmware	*
citrix	application_delivery_controller_firmware	*
citrix	application_delivery_controller	-
citrix	gateway	*
citrix	gateway	*
citrix	gateway	*

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "Citrix ADC, Citrix Gateway",
          "vendor": "n/a",
          "versions": [
            {
              "status": "affected",
              "version": "Citrix ADC 111.1, 2.1, 13.0,13.1"
            }
          ]
        }
      ],
      "source": "support@hackerone.com"
    }
  ],
  "configurations": [
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              "versionEndIncluding": "11.1-65.23",
              "vulnerable": true
            },
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              "versionEndExcluding": "12.1-63.22",
              "versionStartIncluding": "12.1",
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            },
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              "matchCriteriaId": "C2F3ACE6-B0F6-4E27-9DD8-EFEC98A7ACB4",
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              "versionStartIncluding": "12.1",
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            },
            {
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          "negate": false,
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  ],
  "cveTags": [],
  "descriptions": [
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    },
    {
      "lang": "es",
      "value": "Se presenta una vulnerabilidad de denegaci\u00f3n de servicio no autenticada en Citrix ADC versiones anteriores a 13.0-83.27, versiones anteriores a 12.1-63.22 y 11.1-65.23 que, cuando es configurado como servidor virtual VPN (Gateway) o AAA, podr\u00eda permitir a un atacante causar una interrupci\u00f3n temporal de la GUI de administraci\u00f3n, la API Nitro y la comunicaci\u00f3n RPC"
    }
  ],
  "id": "CVE-2021-22955",
  "lastModified": "2026-06-17T03:38:06.187",
  "metrics": {
    "cvssMetricV2": [
      {
        "acInsufInfo": false,
        "baseSeverity": "MEDIUM",
        "cvssData": {
          "accessComplexity": "MEDIUM",
          "accessVector": "NETWORK",
          "authentication": "NONE",
          "availabilityImpact": "PARTIAL",
          "baseScore": 4.3,
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "vectorString": "AV:N/AC:M/Au:N/C:N/I:N/A:P",
          "version": "2.0"
        },
        "exploitabilityScore": 8.6,
        "impactScore": 2.9,
        "obtainAllPrivilege": false,
        "obtainOtherPrivilege": false,
        "obtainUserPrivilege": false,
        "source": "nvd@nist.gov",
        "type": "Primary",
        "userInteractionRequired": false
      }
    ],
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 7.5,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
          "version": "3.1"
        },
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        "impactScore": 3.6,
        "source": "nvd@nist.gov",
        "type": "Primary"
      }
    ]
  },
  "published": "2021-12-07T14:15:08.890",
  "references": [
    {
      "source": "support@hackerone.com",
      "tags": [
        "Vendor Advisory"
      ],
      "url": "https://support.citrix.com/article/CTX330728"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
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      ],
      "url": "https://support.citrix.com/article/CTX330728"
    }
  ],
  "sourceIdentifier": "support@hackerone.com",
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-400"
        }
      ],
      "source": "support@hackerone.com",
      "type": "Secondary"
    },
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-400"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}

CVE-2021-22955 (GCVE-0-2021-22955)

Vulnerability from cvelistv5 – Published: 2021-12-07 13:12 – Updated: 2024-08-03 18:58

Summary

Severity

No CVSS data available.

CWE

CWE-400 - Denial of Service (CWE-400)

Assigner

hackerone mitre root

References

1 reference

URL	Tags
https://support.citrix.com/article/CTX330728	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version
n/a	Citrix ADC, Citrix Gateway	Affected: Citrix ADC 111.1, 2.1, 13.0,13.1

Show details on NVD website

JSON

To clipboard

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            "url": "https://support.citrix.com/article/CTX330728"
          }
        ],
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    ],
    "cna": {
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      "x_legacyV4Record": {
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        "affects": {
          "vendor": {
            "vendor_data": [
              {
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                  "product_data": [
                    {
                      "product_name": "Citrix ADC, Citrix Gateway",
                      "version": {
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}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.