CVE-2026-71285

{
  "id": "CVE-2026-71285",
  "sourceIdentifier": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c",
  "published": "2026-08-05T13:24:53.210",
  "lastModified": "2026-10-23T21:10:00.157",
  "vulnStatus": "Deferred",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Uptime Kuma's Matomo analytics integration (server/analytics/matomo-analytics.js) injects the admin-configurable Matomo value as a bare, unquoted JavaScript expression inside a <script> block rendered on every public status page. A siteId value such as , once saved by an editor/admin, executes arbitrary JavaScript for every unauthenticated visitor of the public /status/<slug> page, enabling session-cookie theft and full page takeover."
    },
    {
      "lang": "es",
      "value": "La integración de análisis Matomo de Uptime Kuma (servidor/analytics/matomo-analytics.js) inyecta el valor “siteId” de Matomo configurable por el administrador como una expresión JavaScript sin formato y sin comillas dentro de un bloque [script_tag] renderizado en cada página de estado pública: “_paq.push([’setSiteId’, ${escapedSiteIdHTMLAttribute}]);”. La cadena de escape utilizada (jsesc con isScriptContext:true, luego html-escaper.escape()) no escapa los caracteres “]”, “)”, “;”, “(”, que son suficientes para salir del contexto de la expresión de array/push. Un valor de siteId como “1]);alert(document.cookie)//”, una vez guardado por un editor/administrador, ejecuta JavaScript arbitrario para cada visitante no autenticado de la página pública /status/[slug], permitiendo el robo de cookies de sesión y la toma de control completa de la página."
    }
  ],
  "affected": [
    {
      "source": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c",
      "affectedData": [
        {
          "vendor": "louislam",
          "product": "uptime-kuma",
          "defaultStatus": "unaffected",
          "programFiles": [
            "server/analytics/matomo-analytics.js"
          ],
          "versions": [
            {
              "version": "0",
              "lessThanOrEqual": "2.4.0",
              "versionType": "semver",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:H/I:H/A:N",
          "baseScore": 8.1,
          "baseSeverity": "HIGH",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "HIGH",
          "userInteraction": "REQUIRED",
          "scope": "CHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "NONE"
        },
        "exploitabilityScore": 1.7,
        "impactScore": 5.8
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-08-05T15:52:03.249974Z",
          "id": "CVE-2026-71285",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-79"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://github.com/louislam/uptime-kuma",
      "source": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c"
    },
    {
      "url": "https://github.com/louislam/uptime-kuma/blob/master/server/analytics/matomo-analytics.js",
      "source": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c"
    }
  ]
}