Vulnerability-Lookup

GSD-2020-13998

Vulnerability from gsd - Updated: 2023-12-13 01:21

Details

** UNSUPPORTED WHEN ASSIGNED ** Citrix XenApp 6.5, when 2FA is enabled, allows a remote unauthenticated attacker to ascertain whether a user exists on the server, because the 2FA error page only occurs after a valid username is entered. NOTE: This vulnerability only affects products that are no longer supported by the maintainer.

Aliases

CVE-2020-13998

Aliases

CVE-2020-13998

JSON

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{
  "GSD": {
    "alias": "CVE-2020-13998",
    "description": "** UNSUPPORTED WHEN ASSIGNED ** Citrix XenApp 6.5, when 2FA is enabled, allows a remote unauthenticated attacker to ascertain whether a user exists on the server, because the 2FA error page only occurs after a valid username is entered. NOTE: This vulnerability only affects products that are no longer supported by the maintainer.",
    "id": "GSD-2020-13998"
  },
  "gsd": {
    "metadata": {
      "exploitCode": "unknown",
      "remediation": "unknown",
      "reportConfidence": "confirmed",
      "type": "vulnerability"
    },
    "osvSchema": {
      "aliases": [
        "CVE-2020-13998"
      ],
      "details": "** UNSUPPORTED WHEN ASSIGNED ** Citrix XenApp 6.5, when 2FA is enabled, allows a remote unauthenticated attacker to ascertain whether a user exists on the server, because the 2FA error page only occurs after a valid username is entered. NOTE: This vulnerability only affects products that are no longer supported by the maintainer.",
      "id": "GSD-2020-13998",
      "modified": "2023-12-13T01:21:46.755162Z",
      "schema_version": "1.4.0"
    }
  },
  "namespaces": {
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        "ID": "CVE-2020-13998",
        "STATE": "PUBLIC"
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            }
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      "data_version": "4.0",
      "description": {
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          {
            "lang": "eng",
            "value": "** UNSUPPORTED WHEN ASSIGNED ** Citrix XenApp 6.5, when 2FA is enabled, allows a remote unauthenticated attacker to ascertain whether a user exists on the server, because the 2FA error page only occurs after a valid username is entered. NOTE: This vulnerability only affects products that are no longer supported by the maintainer."
          }
        ]
      },
      "problemtype": {
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                "value": "n/a"
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      "references": {
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    "nvd.nist.gov": {
      "cve": {
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                "cpeMatch": [
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            "value": "Citrix XenApp 6.5, when 2FA is enabled, allows a remote unauthenticated attacker to ascertain whether a user exists on the server, because the 2FA error page only occurs after a valid username is entered. NOTE: This vulnerability only affects products that are no longer supported by the maintainer"
          },
          {
            "lang": "es",
            "value": "** VERSI\u00d3N NO COMPATIBLE CUANDO SE ASIGN\u00d3 ** Citrix XenApp versi\u00f3n 6.5, cuando 2FA est\u00e1 habilitado, permite a un atacante remoto no autenticado determinar si existe un usuario en el servidor, porque la p\u00e1gina de error 2FA solo se produce despu\u00e9s de ingresar un nombre de usuario v\u00e1lido. NOTA: Esta vulnerabilidad s\u00f3lo afecta a los productos que ya no son apoyados por el mantenedor"
          }
        ],
        "id": "CVE-2020-13998",
        "lastModified": "2024-04-11T01:07:01.070",
        "metrics": {
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              "acInsufInfo": false,
              "baseSeverity": "MEDIUM",
              "cvssData": {
                "accessComplexity": "MEDIUM",
                "accessVector": "NETWORK",
                "authentication": "NONE",
                "availabilityImpact": "NONE",
                "baseScore": 4.3,
                "confidentialityImpact": "PARTIAL",
                "integrityImpact": "NONE",
                "vectorString": "AV:N/AC:M/Au:N/C:P/I:N/A:N",
                "version": "2.0"
              },
              "exploitabilityScore": 8.6,
              "impactScore": 2.9,
              "obtainAllPrivilege": false,
              "obtainOtherPrivilege": false,
              "obtainUserPrivilege": false,
              "source": "nvd@nist.gov",
              "type": "Primary",
              "userInteractionRequired": false
            }
          ],
          "cvssMetricV31": [
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                "attackVector": "NETWORK",
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                "confidentialityImpact": "LOW",
                "integrityImpact": "NONE",
                "privilegesRequired": "NONE",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
                "version": "3.1"
              },
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        "published": "2020-06-11T02:15:10.713",
        "references": [
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            "tags": [
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          }
        ],
        "sourceIdentifier": "cve@mitre.org",
        "vulnStatus": "Modified",
        "weaknesses": [
          {
            "description": [
              {
                "lang": "en",
                "value": "CWE-203"
              }
            ],
            "source": "nvd@nist.gov",
            "type": "Primary"
          }
        ]
      }
    }
  }
}

CVE-2020-13998 (GCVE-0-2020-13998)

Vulnerability from cvelistv5 – Published: 2020-06-11 01:59 – Updated: 2024-08-04 12:32 Unsupported When Assigned

Summary

Citrix XenApp 6.5, when 2FA is enabled, allows a remote unauthenticated attacker to ascertain whether a user exists on the server, because the 2FA error page only occurs after a valid username is entered. NOTE: This vulnerability only affects products that are no longer supported by the maintainer

Severity

7.5 (High)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2024-04-25 17:13 UTC

CWE

n/a
CWE-639 - Authorization Bypass Through User-Controlled Key

Assigner

mitre mitre root

References

1 reference

URL	Tags
https://gist.github.com/kampji/11e259d68ad98a6f0f…	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version
citrix	xenapp	Affected: 6.5.0.0 cpe:2.3:a:citrix:xenapp:6.5.0.0:::::::*

Show details on NVD website

JSON

To clipboard

{
  "containers": {
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      {
        "affected": [
          {
            "cpes": [
              "cpe:2.3:a:citrix:xenapp:6.5.0.0:*:*:*:*:*:*:*"
            ],
            "defaultStatus": "unknown",
            "product": "xenapp",
            "vendor": "citrix",
            "versions": [
              {
                "status": "affected",
                "version": "6.5.0.0"
              }
            ]
          }
        ],
        "metrics": [
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              "attackVector": "NETWORK",
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              "baseScore": 7.5,
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              "confidentialityImpact": "HIGH",
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              "privilegesRequired": "NONE",
              "scope": "UNCHANGED",
              "userInteraction": "NONE",
              "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
              "version": "3.1"
            }
          },
          {
            "other": {
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                "options": [
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                    "Exploitation": "none"
                  },
                  {
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                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2024-04-25T17:13:26.714413Z",
                "version": "2.0.3"
              },
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        "problemTypes": [
          {
            "descriptions": [
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            ]
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        ],
        "providerMetadata": {
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        }
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      "x_legacyV4Record": {
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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.