CVE-2026-49860

{
  "id": "CVE-2026-49860",
  "sourceIdentifier": "[email protected]",
  "published": "2026-06-23T18:18:04.053",
  "lastModified": "2026-10-25T23:10:00.167",
  "vulnStatus": "Analyzed",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Deno is a JavaScript, TypeScript, and WebAssembly runtime. Prior to 2.8.1, when a WebSocket connection was opened, Deno checked the destination hostname against --deny-net rules but did not re-check the IP addresses that hostname resolved to. An attacker-controlled script could use a specially crafted domain name that passes the hostname check yet resolves to a denied IP, bypassing the network restriction entirely. This vulnerability is fixed in 2.8.1."
    },
    {
      "lang": "es",
      "value": "Deno es un entorno de ejecución de JavaScript, TypeScript y WebAssembly. Antes de la 2.8.1, cuando se abría una conexión WebSocket, Deno verificaba el nombre de host de destino contra las reglas --deny-net, pero no volvía a verificar las direcciones IP a las que se resolvía ese nombre de host. Un script controlado por un atacante podría usar un nombre de dominio especialmente diseñado que pasara la verificación del nombre de host pero que se resolviera a una IP denegada, eludiendo por completo la restricción de red. Esta vulnerabilidad está corregida en la versión 2.8.1."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "denoland",
          "product": "deno",
          "versions": [
            {
              "version": "< 2.8.1",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N",
          "baseScore": 5.2,
          "baseSeverity": "MEDIUM",
          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "scope": "CHANGED",
          "confidentialityImpact": "LOW",
          "integrityImpact": "LOW",
          "availabilityImpact": "NONE"
        },
        "exploitabilityScore": 2.0,
        "impactScore": 2.7
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-06-23T17:37:00.680109Z",
          "id": "CVE-2026-49860",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Primary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-918"
        }
      ]
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "operator": "OR",
          "negate": false,
          "cpeMatch": [
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:a:deno:deno:*:*:*:*:*:*:*:*",
              "versionEndExcluding": "2.8.1",
              "matchCriteriaId": "91F453C2-277C-4350-8234-700B47587E97"
            }
          ]
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://github.com/denoland/deno/security/advisories/GHSA-83pc-3rw9-qpwj",
      "source": "[email protected]",
      "tags": [
        "Vendor Advisory"
      ]
    }
  ]
}