« Volver al listado

CVE-2021-26088

Estado: ModificadaCrítica (9.6)—💥 PoC

An improper authentication vulnerability in FSSO Collector version 5.0.295 and below may allow an unauthenticated user to bypass a FSSO firewall policy and access the protected network via sending specifically crafted UDP login notification packets.

CVSS

Probabilidad de explotación (EPSS)

EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).

💥 Exploits públicos

Hay código de explotación o plantillas de detección públicos. No es lo mismo que explotación activa confirmada (KEV), pero aumenta el riesgo: parchee con prioridad.

⚠️ Las pruebas de concepto de GitHub no están verificadas: algunas son falsas o contienen malware. No las ejecute nunca fuera de un laboratorio aislado.

Tecnologías afectadas (1)

Fortinet — Fortinet Single Sign-on

CWE

Referencias

JSON original (NVD)

Mostrar
{
  "id": "CVE-2021-26088",
  "cveTags": [],
  "metrics": {
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2021-26088",
          "role": "CISA Coordinator",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "version": "2.0.3",
          "timestamp": "2024-10-23T13:58:39.555616Z"
        }
      }
    ],
    "cvssMetricV2": [
      {
        "type": "Primary",
        "source": "nvd@nist.gov",
        "cvssData": {
          "version": "2.0",
          "baseScore": 5.8,
          "accessVector": "ADJACENT_NETWORK",
          "vectorString": "AV:A/AC:L/Au:N/C:P/I:P/A:P",
          "authentication": "NONE",
          "integrityImpact": "PARTIAL",
          "accessComplexity": "LOW",
          "availabilityImpact": "PARTIAL",
          "confidentialityImpact": "PARTIAL"
        },
        "acInsufInfo": false,
        "impactScore": 6.4,
        "baseSeverity": "MEDIUM",
        "obtainAllPrivilege": false,
        "exploitabilityScore": 6.5,
        "obtainUserPrivilege": false,
        "obtainOtherPrivilege": false,
        "userInteractionRequired": false
      }
    ],
    "cvssMetricV31": [
      {
        "type": "Secondary",
        "source": "psirt@fortinet.com",
        "cvssData": {
          "scope": "CHANGED",
          "version": "3.1",
          "baseScore": 7.1,
          "attackVector": "ADJACENT_NETWORK",
          "baseSeverity": "HIGH",
          "vectorString": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:L",
          "integrityImpact": "LOW",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "LOW",
          "privilegesRequired": "NONE",
          "confidentialityImpact": "LOW"
        },
        "impactScore": 3.7,
        "exploitabilityScore": 2.8
      },
      {
        "type": "Primary",
        "source": "nvd@nist.gov",
        "cvssData": {
          "scope": "CHANGED",
          "version": "3.1",
          "baseScore": 9.6,
          "attackVector": "ADJACENT_NETWORK",
          "baseSeverity": "CRITICAL",
          "vectorString": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H",
          "integrityImpact": "HIGH",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "confidentialityImpact": "HIGH"
        },
        "impactScore": 6,
        "exploitabilityScore": 2.8
      }
    ]
  },
  "affected": [
    {
      "source": "psirt@fortinet.com",
      "affectedData": [
        {
          "vendor": "Fortinet",
          "product": "Fortinet FSSO Windows DC Agent, FSSO Windows CA",
          "versions": [
            {
              "status": "affected",
              "version": "FSSO Windows DC Agent 5.0.295, 5.0.294; FSSO Windows CA 5.0.295, 5.0.294"
            }
          ]
        }
      ]
    }
  ],
  "published": "2021-07-12T14:15:08.113",
  "references": [
    {
      "url": "https://fortiguard.com/advisory/FG-IR-20-191",
      "tags": [
        "Vendor Advisory"
      ],
      "source": "psirt@fortinet.com"
    },
    {
      "url": "https://fortiguard.com/advisory/FG-IR-20-191",
      "tags": [
        "Vendor Advisory"
      ],
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    }
  ],
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "type": "Primary",
      "source": "nvd@nist.gov",
      "description": [
        {
          "lang": "en",
          "value": "CWE-287"
        }
      ]
    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "An improper authentication vulnerability in FSSO Collector version 5.0.295 and below may allow an unauthenticated user to bypass a FSSO firewall policy and access the protected network via sending specifically crafted UDP login notification packets."
    },
    {
      "lang": "es",
      "value": "Una vulnerabilidad de autenticación inapropiada en FSSO Collector versiones 5.0.295 de  y posteriores, puede permitir a un usuario no autenticado omitir una política de firewall de FSSO y acceder a la red protegida por medio del envío de paquetes de notificación de inicio de sesión UDP específicamente diseñados"
    }
  ],
  "lastModified": "2026-06-17T03:42:50.427",
  "configurations": [
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:fortinet:fortinet_single_sign-on:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "B9C9AF5B-2891-4908-B559-186BD7B3CF3A",
              "versionEndExcluding": "6.4.6"
            },
            {
              "criteria": "cpe:2.3:a:fortinet:fortinet_single_sign-on:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "B8245F68-9860-40E6-9F45-8B1789FA5620",
              "versionEndExcluding": "7.0.1",
              "versionStartIncluding": "7.0.0"
            }
          ],
          "operator": "OR"
        }
      ]
    }
  ],
  "sourceIdentifier": "psirt@fortinet.com"
}