CVE-2026-40303

{
  "id": "CVE-2026-40303",
  "sourceIdentifier": "[email protected]",
  "published": "2026-04-17T21:16:35.140",
  "lastModified": "2026-10-26T22:10:00.163",
  "vulnStatus": "Analyzed",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "zrok is software for sharing web services, files, and network resources. Prior to version 2.0.1, endpoints.GetSessionCookie parses an attacker-supplied cookie chunk count and calls make([]string, count) with no upper bound before any token validation occurs. The function is reached on every request to an OAuth-protected proxy share, allowing an unauthenticated remote attacker to trigger gigabyte-scale heap allocations per request, leading to process-level OOM termination or repeated goroutine panics. Both publicProxy and dynamicProxy are affected. Version 2.0.1 patches the issue."
    },
    {
      "lang": "es",
      "value": "zrok es un software para compartir servicios web, archivos y recursos de red. Antes de la versión 2.0.1, endpoints.GetSessionCookie analiza un recuento de fragmentos de cookie proporcionado por un atacante y llama a make([]string, count) sin un límite superior antes de que ocurra cualquier validación de token. Se accede a la función en cada solicitud a un recurso compartido de proxy protegido por OAuth, lo que permite a un atacante remoto no autenticado activar asignaciones de memoria heap a escala de gigabytes por solicitud, lo que lleva a la terminación OOM a nivel de proceso o a pánicos repetidos de goroutine. Tanto publicProxy como dynamicProxy se ven afectados. La versión 2.0.1 corrige el problema."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "openziti",
          "product": "zrok",
          "versions": [
            {
              "version": "< 2.0.1",
              "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:N/A:H",
          "baseScore": 7.5,
          "baseSeverity": "HIGH",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 3.6
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-04-20T16:18:59.334800Z",
          "id": "CVE-2026-40303",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-400"
        },
        {
          "lang": "en",
          "value": "CWE-789"
        }
      ]
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "operator": "OR",
          "negate": false,
          "cpeMatch": [
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:a:netfoundry:zrok:*:*:*:*:*:*:*:*",
              "versionEndExcluding": "2.0.1",
              "matchCriteriaId": "70C6F018-6D34-4A75-A49D-A795B0A5B056"
            }
          ]
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://github.com/openziti/zrok/releases/tag/v2.0.1",
      "source": "[email protected]",
      "tags": [
        "Release Notes"
      ]
    },
    {
      "url": "https://github.com/openziti/zrok/security/advisories/GHSA-cpf9-ph2j-ccr9",
      "source": "[email protected]",
      "tags": [
        "Vendor Advisory"
      ]
    }
  ]
}