CVE-2026-34121

{
  "id": "CVE-2026-34121",
  "sourceIdentifier": "f23511db-6c3e-4e32-a477-6aa17d310630",
  "published": "2026-04-02T18:16:28.990",
  "lastModified": "2026-11-02T22:17:21.603",
  "vulnStatus": "Modified",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "An authentication bypass vulnerability within the HTTP handling of the DS configuration service in TP-Link Tapo C520WS v2.6 and C210 v3 was identified, due to inconsistent parsing and authorization logic in JSON requests during authentication check.  An unauthenticated attacker can append an authentication-exempt action to a request containing privileged DS do actions, bypassing authorization checks.\n\nSuccessful exploitation allows unauthenticated execution of restricted configuration actions, which may result in unauthorized modification of device state."
    },
    {
      "lang": "es",
      "value": "Una vulnerabilidad de omisión de autenticación dentro del manejo HTTP del servicio de configuración DS en TP-Link Tapo C520WS v2.6 fue identificada, debido a una lógica de análisis y autorización inconsistente en las solicitudes JSON durante la verificación de autenticación. Un atacante no autenticado puede adjuntar una acción exenta de autenticación a una solicitud que contiene acciones privilegiadas de 'DS do', omitiendo las verificaciones de autorización.\n\nLa explotación exitosa permite la ejecución no autenticada de acciones de configuración restringidas, lo que puede resultar en una modificación no autorizada del estado del dispositivo."
    }
  ],
  "affected": [
    {
      "source": "f23511db-6c3e-4e32-a477-6aa17d310630",
      "affectedData": [
        {
          "vendor": "TP-Link Systems Inc.",
          "product": "Tapo C520WS v2.6",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "0",
              "lessThan": "1.2.4 Build 260326 Rel.24666n",
              "versionType": "custom",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "TP Link Systems Inc.",
          "product": "Tapo C210 v3.6",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "0",
              "lessThan": "1.2.7 Build 260818 Rel.64715n",
              "versionType": "custom",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
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          "baseScore": 8.7,
          "baseSeverity": "HIGH",
          "attackVector": "ADJACENT",
          "attackComplexity": "LOW",
          "attackRequirements": "NONE",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "vulnConfidentialityImpact": "HIGH",
          "vulnIntegrityImpact": "HIGH",
          "vulnAvailabilityImpact": "HIGH",
          "subConfidentialityImpact": "NONE",
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          "subAvailabilityImpact": "NONE",
          "exploitMaturity": "NOT_DEFINED",
          "confidentialityRequirement": "NOT_DEFINED",
          "integrityRequirement": "NOT_DEFINED",
          "availabilityRequirement": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
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          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
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          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
          "Automatable": "NOT_DEFINED",
          "Recovery": "NOT_DEFINED",
          "valueDensity": "NOT_DEFINED",
          "vulnerabilityResponseEffort": "NOT_DEFINED",
          "providerUrgency": "NOT_DEFINED"
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          "scope": "UNCHANGED",
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        "ssvcData": {
          "timestamp": "2026-04-02T17:58:42.273820Z",
          "id": "CVE-2026-34121",
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            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
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            {
              "technicalImpact": "total"
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          "role": "CISA Coordinator",
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      "description": [
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          "value": "CWE-287"
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  "references": [
    {
      "url": "https://www.tp-link.com/en/support/download/tapo-c520ws/#Firmware-Release-Notes",
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      "url": "https://www.tp-link.com/us/support/faq/5047/",
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