CVE-2026-6242 (GCVE-0-2026-6242)

Vulnerability from cvelistv5 – Published: 2026-06-05 23:52 – Updated: 2026-06-08 13:17
VLAI
Title
Authenticated Format String Vulnerability in ONVIF Subscribe Service on TP-Link Tapo C520WS
Summary
An authenticated format string vulnerability exists in the ONVIF Subscribe service in Tapo C520WS v2 due to improper handling of externally supplied parameters within formatting functions. An attacker may inject crafted format strings into event subscription requests or notification generation path to disrupt normal service execution. Successful exploitation may cause the event notification service to terminate unexpectedly, resulting in the loss of real-time alarm functionality and disruption of event notifications.
Severity
6.8 (Medium)
CVSS:4.0/AV:A/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-134 - Use of Externally-Controlled format string
Assigner
References
Impacted products
Vendor Product Version
TP-Link Systems Inc. Tapo C520WS v2 Affected: 0 , < 1.2.6 Build 260528 (custom)
Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-6242",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-06-08T13:17:05.938418Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-06-08T13:17:15.157Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Tapo C520WS v2",
          "vendor": "TP-Link Systems Inc.",
          "versions": [
            {
              "lessThan": "1.2.6 Build 260528",
              "status": "affected",
              "version": "0",
              "versionType": "custom"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "\u003cp\u003eAn authenticated format string vulnerability exists in the ONVIF Subscribe service in Tapo C520WS v2 due to improper handling of externally supplied parameters within formatting functions. An attacker may inject crafted format strings into event subscription requests or notification generation path to disrupt normal service execution.\n\u003cbr\u003eSuccessful exploitation may cause the event notification service to terminate unexpectedly, resulting in the loss of real-time alarm functionality and disruption of event notifications.\u0026nbsp;\u003cbr\u003e\u003c/p\u003e"
            }
          ],
          "value": "An authenticated format string vulnerability exists in the ONVIF Subscribe service in Tapo C520WS v2 due to improper handling of externally supplied parameters within formatting functions. An attacker may inject crafted format strings into event subscription requests or notification generation path to disrupt normal service execution.\n\nSuccessful exploitation may cause the event notification service to terminate unexpectedly, resulting in the loss of real-time alarm functionality and disruption of event notifications."
        }
      ],
      "impacts": [
        {
          "capecId": "CAPEC-135",
          "descriptions": [
            {
              "lang": "en",
              "value": "CAPEC-135 Format String Injection"
            }
          ]
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "Automatable": "NOT_DEFINED",
            "Recovery": "NOT_DEFINED",
            "Safety": "NOT_DEFINED",
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "ADJACENT",
            "baseScore": 6.8,
            "baseSeverity": "MEDIUM",
            "exploitMaturity": "NOT_DEFINED",
            "privilegesRequired": "HIGH",
            "providerUrgency": "NOT_DEFINED",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "valueDensity": "NOT_DEFINED",
            "vectorString": "CVSS:4.0/AV:A/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "HIGH",
            "vulnConfidentialityImpact": "NONE",
            "vulnIntegrityImpact": "NONE",
            "vulnerabilityResponseEffort": "NOT_DEFINED"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-134",
              "description": "CWE-134 Use of Externally-Controlled format string",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-06-05T23:52:36.290Z",
        "orgId": "f23511db-6c3e-4e32-a477-6aa17d310630",
        "shortName": "TPLink"
      },
      "references": [
        {
          "tags": [
            "patch"
          ],
          "url": "https://www.tp-link.com/us/support/download/tapo-c520ws/#Firmware-Release-Notes"
        },
        {
          "tags": [
            "patch"
          ],
          "url": "https://www.tp-link.com/en/support/download/tapo-c520ws/#Firmware-Release-Notes"
        },
        {
          "tags": [
            "vendor-advisory"
          ],
          "url": "https://www.tp-link.com/us/support/faq/5120/"
        }
      ],
      "source": {
        "discovery": "UNKNOWN"
      },
      "title": "Authenticated Format String Vulnerability in ONVIF Subscribe Service on TP-Link Tapo C520WS",
      "x_generator": {
        "engine": "Vulnogram 1.0.1"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "f23511db-6c3e-4e32-a477-6aa17d310630",
    "assignerShortName": "TPLink",
    "cveId": "CVE-2026-6242",
    "datePublished": "2026-06-05T23:52:36.290Z",
    "dateReserved": "2026-04-13T17:10:28.804Z",
    "dateUpdated": "2026-06-08T13:17:15.157Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-6242",
      "date": "2026-07-30",
      "epss": "0.00174",
      "percentile": "0.07104"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-6242\",\"sourceIdentifier\":\"f23511db-6c3e-4e32-a477-6aa17d310630\",\"published\":\"2026-06-06T00:16:41.347\",\"lastModified\":\"2026-07-23T07:10:00.113\",\"vulnStatus\":\"Deferred\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"An authenticated format string vulnerability exists in the ONVIF Subscribe service in Tapo C520WS v2 due to improper handling of externally supplied parameters within formatting functions. An attacker may inject crafted format strings into event subscription requests or notification generation path to disrupt normal service execution.\\n\\nSuccessful exploitation may cause the event notification service to terminate unexpectedly, resulting in the loss of real-time alarm functionality and disruption of event notifications.\"},{\"lang\":\"es\",\"value\":\"Existe una vulnerabilidad de cadena de formato autenticada en el servicio ONVIF Subscribe en Tapo C520WS v2 debido al manejo inadecuado de par\u00e1metros suministrados externamente dentro de funciones de formato. Un atacante puede inyectar cadenas de formato manipuladas en solicitudes de suscripci\u00f3n de eventos o en la ruta de generaci\u00f3n de notificaciones para interrumpir la ejecuci\u00f3n normal del servicio. La explotaci\u00f3n exitosa puede causar que el servicio de notificaci\u00f3n de eventos termine inesperadamente, lo que resulta en la p\u00e9rdida de la funcionalidad de alarma en tiempo real y la interrupci\u00f3n de las notificaciones de eventos.\"}],\"affected\":[{\"source\":\"f23511db-6c3e-4e32-a477-6aa17d310630\",\"affectedData\":[{\"vendor\":\"TP-Link Systems Inc.\",\"product\":\"Tapo C520WS v2\",\"defaultStatus\":\"unaffected\",\"versions\":[{\"version\":\"0\",\"lessThan\":\"1.2.6 Build 260528\",\"versionType\":\"custom\",\"status\":\"affected\"}]}]}],\"metrics\":{\"cvssMetricV40\":[{\"source\":\"f23511db-6c3e-4e32-a477-6aa17d310630\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"4.0\",\"vectorString\":\"CVSS:4.0/AV:A/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X\",\"baseScore\":6.8,\"baseSeverity\":\"MEDIUM\",\"attackVector\":\"ADJACENT\",\"attackComplexity\":\"LOW\",\"attackRequirements\":\"NONE\",\"privilegesRequired\":\"HIGH\",\"userInteraction\":\"NONE\",\"vulnConfidentialityImpact\":\"NONE\",\"vulnIntegrityImpact\":\"NONE\",\"vulnAvailabilityImpact\":\"HIGH\",\"subConfidentialityImpact\":\"NONE\",\"subIntegrityImpact\":\"NONE\",\"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\",\"modifiedVulnConfidentialityImpact\":\"NOT_DEFINED\",\"modifiedVulnIntegrityImpact\":\"NOT_DEFINED\",\"modifiedVulnAvailabilityImpact\":\"NOT_DEFINED\",\"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\"}}],\"ssvcV203\":[{\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\",\"ssvcData\":{\"timestamp\":\"2026-06-08T13:17:05.938418Z\",\"id\":\"CVE-2026-6242\",\"options\":[{\"exploitation\":\"none\"},{\"automatable\":\"no\"},{\"technicalImpact\":\"partial\"}],\"role\":\"CISA Coordinator\",\"version\":\"2.0.3\"}}]},\"weaknesses\":[{\"source\":\"f23511db-6c3e-4e32-a477-6aa17d310630\",\"type\":\"Secondary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-134\"}]}],\"references\":[{\"url\":\"https://www.tp-link.com/en/support/download/tapo-c520ws/#Firmware-Release-Notes\",\"source\":\"f23511db-6c3e-4e32-a477-6aa17d310630\"},{\"url\":\"https://www.tp-link.com/us/support/download/tapo-c520ws/#Firmware-Release-Notes\",\"source\":\"f23511db-6c3e-4e32-a477-6aa17d310630\"},{\"url\":\"https://www.tp-link.com/us/support/faq/5120/\",\"source\":\"f23511db-6c3e-4e32-a477-6aa17d310630\"}]}}",
    "redhat_vex": {
      "current_release_date": "2026-06-07T00:43:28+00:00",
      "cve": "CVE-2026-6242",
      "id": "CVE-2026-6242",
      "initial_release_date": "2026-01-01T00:00:00+00:00",
      "product_status:known_not_affected": "1",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "Authenticated Format String Vulnerability in ONVIF Subscribe Service on TP-Link Tapo C520WS",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-6242.json",
      "version": "3"
    },
    "vulnrichment": {
      "containers": "{\"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-6242\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"none\"}, {\"Automatable\": \"no\"}, {\"Technical Impact\": \"partial\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-06-08T13:17:05.938418Z\"}}}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2026-06-08T13:17:11.849Z\"}}], \"cna\": {\"title\": \"Authenticated Format String Vulnerability in ONVIF Subscribe Service on TP-Link Tapo C520WS\", \"source\": {\"discovery\": \"UNKNOWN\"}, \"impacts\": [{\"capecId\": \"CAPEC-135\", \"descriptions\": [{\"lang\": \"en\", \"value\": \"CAPEC-135 Format String Injection\"}]}], \"metrics\": [{\"format\": \"CVSS\", \"cvssV4_0\": {\"Safety\": \"NOT_DEFINED\", \"version\": \"4.0\", \"Recovery\": \"NOT_DEFINED\", \"baseScore\": 6.8, \"Automatable\": \"NOT_DEFINED\", \"attackVector\": \"ADJACENT\", \"baseSeverity\": \"MEDIUM\", \"valueDensity\": \"NOT_DEFINED\", \"vectorString\": \"CVSS:4.0/AV:A/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N\", \"exploitMaturity\": \"NOT_DEFINED\", \"providerUrgency\": \"NOT_DEFINED\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"LOW\", \"attackRequirements\": \"NONE\", \"privilegesRequired\": \"HIGH\", \"subIntegrityImpact\": \"NONE\", \"vulnIntegrityImpact\": \"NONE\", \"subAvailabilityImpact\": \"NONE\", \"vulnAvailabilityImpact\": \"HIGH\", \"subConfidentialityImpact\": \"NONE\", \"vulnConfidentialityImpact\": \"NONE\", \"vulnerabilityResponseEffort\": \"NOT_DEFINED\"}, \"scenarios\": [{\"lang\": \"en\", \"value\": \"GENERAL\"}]}], \"affected\": [{\"vendor\": \"TP-Link Systems Inc.\", \"product\": \"Tapo C520WS v2\", \"versions\": [{\"status\": \"affected\", \"version\": \"0\", \"lessThan\": \"1.2.6 Build 260528\", \"versionType\": \"custom\"}], \"defaultStatus\": \"unaffected\"}], \"references\": [{\"url\": \"https://www.tp-link.com/us/support/download/tapo-c520ws/#Firmware-Release-Notes\", \"tags\": [\"patch\"]}, {\"url\": \"https://www.tp-link.com/en/support/download/tapo-c520ws/#Firmware-Release-Notes\", \"tags\": [\"patch\"]}, {\"url\": \"https://www.tp-link.com/us/support/faq/5120/\", \"tags\": [\"vendor-advisory\"]}], \"x_generator\": {\"engine\": \"Vulnogram 1.0.1\"}, \"descriptions\": [{\"lang\": \"en\", \"value\": \"An authenticated format string vulnerability exists in the ONVIF Subscribe service in Tapo C520WS v2 due to improper handling of externally supplied parameters within formatting functions. An attacker may inject crafted format strings into event subscription requests or notification generation path to disrupt normal service execution.\\n\\nSuccessful exploitation may cause the event notification service to terminate unexpectedly, resulting in the loss of real-time alarm functionality and disruption of event notifications.\", \"supportingMedia\": [{\"type\": \"text/html\", \"value\": \"\u003cp\u003eAn authenticated format string vulnerability exists in the ONVIF Subscribe service in Tapo C520WS v2 due to improper handling of externally supplied parameters within formatting functions. An attacker may inject crafted format strings into event subscription requests or notification generation path to disrupt normal service execution.\\n\u003cbr\u003eSuccessful exploitation may cause the event notification service to terminate unexpectedly, resulting in the loss of real-time alarm functionality and disruption of event notifications.\u0026nbsp;\u003cbr\u003e\u003c/p\u003e\", \"base64\": false}]}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-134\", \"description\": \"CWE-134 Use of Externally-Controlled format string\"}]}], \"providerMetadata\": {\"orgId\": \"f23511db-6c3e-4e32-a477-6aa17d310630\", \"shortName\": \"TPLink\", \"dateUpdated\": \"2026-06-05T23:52:36.290Z\"}}}",
      "cveMetadata": "{\"cveId\": \"CVE-2026-6242\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-06-08T13:17:15.157Z\", \"dateReserved\": \"2026-04-13T17:10:28.804Z\", \"assignerOrgId\": \"f23511db-6c3e-4e32-a477-6aa17d310630\", \"datePublished\": \"2026-06-05T23:52:36.290Z\", \"assignerShortName\": \"TPLink\"}",
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.