FKIE_CVE-2026-33250

Vulnerability from fkie_nvd - Published: 2026-03-24 00:16 - Updated: 2026-06-17 10:37
Severity
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Summary
Freeciv21 is a free open source, turn-based, empire-building strategy game. Versions prior to 3.1.1 crash with a stack overflow when receiving specially-crafted packets. A remote attacker can use this to take down any public server. A malicious server can use this to crash the game on the player's machine. Authentication is not needed and, by default, logs do not contain any useful information. All users should upgrade to Freeciv21 version 3.1.1. Running the server behind a firewall can help mitigate the issue for non-public servers. For local games, Freeciv21 restricts connections to the current user and is therefore not affected.
References
security-advisories@github.comhttps://github.com/longturn/freeciv21/commit/ad8e18ca22595529599782b2984bf44df8d69ed6
security-advisories@github.comhttps://github.com/longturn/freeciv21/releases/tag/v3.1.1
security-advisories@github.comhttps://github.com/longturn/freeciv21/security/advisories/GHSA-f76g-6w3f-f6r3
security-advisories@github.comhttps://redmine.freeciv.org/issues/1955
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "freeciv21",
          "vendor": "longturn",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 3.1.1"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Freeciv21 is a free open source, turn-based, empire-building strategy game. Versions prior to 3.1.1 crash with a stack overflow when receiving specially-crafted packets. A remote attacker can use this to take down any public server. A malicious server can use this to crash the game on the player\u0027s machine. Authentication is not needed and, by default, logs do not contain any useful information. All users should upgrade to Freeciv21 version 3.1.1. Running the server behind a firewall can help mitigate the issue for non-public servers. For local games, Freeciv21 restricts connections to the current user and is therefore not affected."
    },
    {
      "lang": "es",
      "value": "Freeciv21 es un juego de estrategia gratuito de c\u00f3digo abierto, por turnos, de construcci\u00f3n de imperios. Las versiones anteriores a la 3.1.1 fallan con un desbordamiento de pila al recibir paquetes especialmente dise\u00f1ados. Un atacante remoto puede usar esto para derribar cualquier servidor p\u00fablico. Un servidor malicioso puede usar esto para bloquear el juego en la m\u00e1quina del jugador. No se necesita autenticaci\u00f3n y, por defecto, los registros no contienen ninguna informaci\u00f3n \u00fatil. Todos los usuarios deber\u00edan actualizar a la versi\u00f3n 3.1.1 de Freeciv21. Ejecutar el servidor detr\u00e1s de un cortafuegos puede ayudar a mitigar el problema para servidores no p\u00fablicos. Para juegos locales, Freeciv21 restringe las conexiones al usuario actual y por lo tanto no se ve afectado."
    }
  ],
  "id": "CVE-2026-33250",
  "lastModified": "2026-06-17T10:37:11.590",
  "metrics": {
    "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"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 3.6,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-33250",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-03-24T13:36:15.835264Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-03-24T00:16:29.830",
  "references": [
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/longturn/freeciv21/commit/ad8e18ca22595529599782b2984bf44df8d69ed6"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/longturn/freeciv21/releases/tag/v3.1.1"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/longturn/freeciv21/security/advisories/GHSA-f76g-6w3f-f6r3"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://redmine.freeciv.org/issues/1955"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Deferred",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-20"
        },
        {
          "lang": "en",
          "value": "CWE-121"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Secondary"
    }
  ]
}



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