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FKIE_CVE-2020-27121

Vulnerability from fkie_nvd - Published: 2020-11-06 19:15 - Updated: 2026-06-17 03:08
Summary
A vulnerability in Cisco Unified Communications Manager IM & Presence Service (Unified CM IM&P) Software could allow an authenticated, remote attacker to cause the Cisco XCP Authentication Service on an affected device to restart, resulting in a denial of service (DoS) condition. The vulnerability is due to improper handling of login requests. An attacker could exploit this vulnerability by sending a crafted client login request to an affected device. A successful exploit could allow the attacker to cause a process to crash, resulting in a DoS condition for new login attempts. Users who are authenticated at the time of the attack would not be affected. There are workarounds that address this vulnerability.
Impacted products

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "Cisco Unified Communications Manager IM and Presence Service",
          "vendor": "Cisco",
          "versions": [
            {
              "status": "affected",
              "version": "n/a"
            }
          ]
        }
      ],
      "source": "psirt@cisco.com"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:cisco:unified_communications_manager_im_and_presence_service:12.5\\(1\\):*:*:*:*:*:*:*",
              "matchCriteriaId": "CAAAAF61-C33F-462B-B7C4-9F976235888A",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "A vulnerability in Cisco Unified Communications Manager IM \u0026amp; Presence Service (Unified CM IM\u0026amp;P) Software could allow an authenticated, remote attacker to cause the Cisco XCP Authentication Service on an affected device to restart, resulting in a denial of service (DoS) condition. The vulnerability is due to improper handling of login requests. An attacker could exploit this vulnerability by sending a crafted client login request to an affected device. A successful exploit could allow the attacker to cause a process to crash, resulting in a DoS condition for new login attempts. Users who are authenticated at the time of the attack would not be affected. There are workarounds that address this vulnerability."
    },
    {
      "lang": "es",
      "value": "Una vulnerabilidad en Cisco Unified Communications Manager IM \u0026amp; Presence Service (Unified CM IM\u0026amp;P) Software podr\u00eda permitir a un atacante remoto autenticado causar que Cisco XCP Authentication Service en un dispositivo afectado se reinicie, resultando en una condici\u00f3n de denegaci\u00f3n de servicio (DoS).\u0026#xa0;La vulnerabilidad es debido al manejo inapropiado de las peticiones de inicio de sesi\u00f3n.\u0026#xa0;Un atacante podr\u00eda explotar esta vulnerabilidad mediante el env\u00edo de una petici\u00f3n de inicio de sesi\u00f3n de cliente dise\u00f1ada hacia un dispositivo afectado.\u0026#xa0;Una explotaci\u00f3n con \u00e9xito podr\u00eda permitir al atacante causar que un proceso se bloquee, resultando en una condici\u00f3n de DoS para nuevos intentos de inicio de sesi\u00f3n.\u0026#xa0;Los usuarios que est\u00e9n autenticados en el momento del ataque no ser\u00edan afectados.\u0026#xa0;Existen soluciones que abordan esta vulnerabilidad"
    }
  ],
  "id": "CVE-2020-27121",
  "lastModified": "2026-06-17T03:08:49.720",
  "metrics": {
    "cvssMetricV2": [
      {
        "acInsufInfo": false,
        "baseSeverity": "MEDIUM",
        "cvssData": {
          "accessComplexity": "LOW",
          "accessVector": "NETWORK",
          "authentication": "SINGLE",
          "availabilityImpact": "PARTIAL",
          "baseScore": 4.0,
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "vectorString": "AV:N/AC:L/Au:S/C:N/I:N/A:P",
          "version": "2.0"
        },
        "exploitabilityScore": 8.0,
        "impactScore": 2.9,
        "obtainAllPrivilege": false,
        "obtainOtherPrivilege": false,
        "obtainUserPrivilege": false,
        "source": "nvd@nist.gov",
        "type": "Primary",
        "userInteractionRequired": false
      }
    ],
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "LOW",
          "baseScore": 4.3,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L",
          "version": "3.1"
        },
        "exploitabilityScore": 2.8,
        "impactScore": 1.4,
        "source": "psirt@cisco.com",
        "type": "Secondary"
      },
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 6.5,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 2.8,
        "impactScore": 3.6,
        "source": "nvd@nist.gov",
        "type": "Primary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2020-27121",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2024-11-13T17:22:36.184575Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2020-11-06T19:15:13.360",
  "references": [
    {
      "source": "psirt@cisco.com",
      "tags": [
        "Vendor Advisory"
      ],
      "url": "https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-imp-dos-uTx2dqu2"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Vendor Advisory"
      ],
      "url": "https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-imp-dos-uTx2dqu2"
    }
  ],
  "sourceIdentifier": "psirt@cisco.com",
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-248"
        }
      ],
      "source": "psirt@cisco.com",
      "type": "Secondary"
    },
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-755"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}



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