CVE-2026-49819

{
  "id": "CVE-2026-49819",
  "sourceIdentifier": "[email protected]",
  "published": "2026-08-13T00:17:32.747",
  "lastModified": "2026-10-24T16:10:00.153",
  "vulnStatus": "Deferred",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "UpSnap is a wake on lan web app. Versions 4.4.1 through 5.3.5 are vulnerable to a missing-authentication / privilege-escalation chain in `pb.HandlerInitSuperuser` (`backend/pb/handlers.go:249`), reachable as `POST /api/upsnap/init-superuser`. The vulnerable code lacks any authentication, setup token, IP allow-list, or rate limit and is gated only by a `totalSuperusers > 0` count check — a condition that is false on every fresh install — allowing an unauthenticated network-adjacent attacker to register the initial superuser account, receive a long-lived JWT, and pivot to root remote code execution at `backend/networking/wake.go:43` (`exec.CommandContext(ctx, \"/bin/sh\", \"-c\", wake_cmd)`). Version 5.4.0 fixes the issue."
    },
    {
      "lang": "es",
      "value": "UpSnap es una aplicación web de wake on lan. Las versiones 4.4.1 a la 5.3.5 son vulnerables a una cadena de falta de autenticación / escalada de privilegios en “pb.HandlerInitSuperuser” (“backend/pb/handlers.go:249”), accesible como “POST /api/upsnap/init-superuser”. El código vulnerable carece de cualquier autenticación, token de configuración, lista de permitidos de IP, o límite de tasa y está restringido solo por una verificación de conteo “totalSuperusers mayor que 0” - una condición que es falsa en cada instalación nueva - permitiendo a un atacante adyacente a la red no autenticado registrar la cuenta de superusuario inicial, recibir un JWT de larga duración, y pivotar a ejecución remota de código como root en “backend/networking/wake.go:43” (“exec.CommandContext(ctx, “/bin/sh”, “-c”, wake_cmd)”). La versión 5.4.0 corrige el problema."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "seriousm4x",
          "product": "UpSnap",
          "versions": [
            {
              "version": ">= 4.4.1, < 5.4.0",
              "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:H/I:H/A:H",
          "baseScore": 9.8,
          "baseSeverity": "CRITICAL",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 5.9
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-08-13T13:08:41.648461Z",
          "id": "CVE-2026-49819",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-78"
        },
        {
          "lang": "en",
          "value": "CWE-269"
        },
        {
          "lang": "en",
          "value": "CWE-306"
        },
        {
          "lang": "en",
          "value": "CWE-862"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://github.com/seriousm4x/UpSnap/releases/tag/5.4.0",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/seriousm4x/UpSnap/security/advisories/GHSA-w4jr-728f-5jhq",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/seriousm4x/UpSnap/security/advisories/GHSA-w4jr-728f-5jhq",
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"
    }
  ]
}