CVE-2026-27890

{
  "id": "CVE-2026-27890",
  "sourceIdentifier": "[email protected]",
  "published": "2026-04-17T19:16:34.993",
  "lastModified": "2026-10-26T21:10:00.170",
  "vulnStatus": "Analyzed",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Firebird is an open-source relational database management system. In versions prior to 5.0.4, 4.0.7 and 3.0.14, when processing CNCT_specific_data segments during authentication, the server assumes segments arrive in strictly ascending order. If segments arrive out of order, the Array class's grow() method computes a negative size value, causing a SIGSEGV crash. An unauthenticated attacker who knows only the server's IP and port can exploit this to crash the server. This issue has been fixed in versions 5.0.4, 4.0.7 and 3.0.14."
    },
    {
      "lang": "es",
      "value": "Firebird es un sistema de gestión de bases de datos relacionales de código abierto. En versiones anteriores a la 5.0.4, 4.0.7 y 3.0.14, al procesar segmentos CNCT_specific_data durante la autenticación, el servidor asume que los segmentos llegan en orden estrictamente ascendente. Si los segmentos llegan desordenados, el método grow() de la clase Array calcula un valor de tamaño negativo, causando un fallo SIGSEGV. Un atacante no autenticado que conoce solo la IP y el puerto del servidor puede explotar esto para bloquear el servidor. Este problema ha sido solucionado en las versiones 5.0.4, 4.0.7 y 3.0.14."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "FirebirdSQL",
          "product": "firebird",
          "versions": [
            {
              "version": ">= 3.0.0, < 3.0.14",
              "status": "affected"
            },
            {
              "version": ">= 4.0.0, < 4.0.7",
              "status": "affected"
            },
            {
              "version": ">= 5.0.0, < 5.0.4",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H",
          "baseScore": 8.2,
          "baseSeverity": "HIGH",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "NONE",
          "integrityImpact": "LOW",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 4.2
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-04-17T18:50:13.916401Z",
          "id": "CVE-2026-27890",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-119"
        },
        {
          "lang": "en",
          "value": "CWE-787"
        }
      ]
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "operator": "OR",
          "negate": false,
          "cpeMatch": [
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              "vulnerable": true,
              "criteria": "cpe:2.3:a:firebirdsql:firebird:*:*:*:*:*:*:*:*",
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              "matchCriteriaId": "53D811A2-F880-46E9-9F7F-1CE3AC487F67"
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  "references": [
    {
      "url": "https://github.com/FirebirdSQL/firebird/releases/tag/v3.0.14",
      "source": "[email protected]",
      "tags": [
        "Release Notes"
      ]
    },
    {
      "url": "https://github.com/FirebirdSQL/firebird/releases/tag/v4.0.7",
      "source": "[email protected]",
      "tags": [
        "Release Notes"
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    {
      "url": "https://github.com/FirebirdSQL/firebird/releases/tag/v5.0.4",
      "source": "[email protected]",
      "tags": [
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    },
    {
      "url": "https://github.com/FirebirdSQL/firebird/security/advisories/GHSA-6crx-4g37-7j49",
      "source": "[email protected]",
      "tags": [
        "Exploit",
        "Vendor Advisory"
      ]
    }
  ]
}