{"api_version":"1","generated_at":"2026-06-24T18:55:28+00:00","cve":"CVE-2026-6240","urls":{"html":"https://cve.report/CVE-2026-6240","api":"https://cve.report/api/cve/CVE-2026-6240.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-6240","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-6240"},"summary":{"title":"Authenticated Stack-based Buffer Overflow in ONVIF DeleteUsers Service on TP-Link Tapo C520WS","description":"A stack-based buffer overflow vulnerability exists in Tapo C520WS v2 in the ONVIF DeleteUsers service, due to insufficient boundary checks when handling multiple user deletion parameters. An authenticated attacker can send a  crafted malicious request containing an excessive number of identifiers to overflow stack memory.\n\nSuccessful exploitation may result in a service crash or deadlock, leading to DoS affecting device management and monitoring functionality.","state":"PUBLISHED","assigner":"TPLink","published_at":"2026-06-06 00:16:41","updated_at":"2026-06-08 15:01:06"},"problem_types":["CWE-121","CWE-121 CWE-121 Stack-based buffer overflow"],"metrics":[{"version":"4.0","source":"f23511db-6c3e-4e32-a477-6aa17d310630","type":"Secondary","score":"6.8","severity":"MEDIUM","vector":"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","data":{"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"}},{"version":"4.0","source":"CNA","type":"CVSS","score":"6.8","severity":"MEDIUM","vector":"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","data":{"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"}}],"references":[{"url":"https://www.tp-link.com/us/support/faq/5120/","name":"https://www.tp-link.com/us/support/faq/5120/","refsource":"f23511db-6c3e-4e32-a477-6aa17d310630","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.tp-link.com/en/support/download/tapo-c520ws/#Firmware-Release-Notes","name":"https://www.tp-link.com/en/support/download/tapo-c520ws/#Firmware-Release-Notes","refsource":"f23511db-6c3e-4e32-a477-6aa17d310630","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.tp-link.com/us/support/download/tapo-c520ws/#Firmware-Release-Notes","name":"https://www.tp-link.com/us/support/download/tapo-c520ws/#Firmware-Release-Notes","refsource":"f23511db-6c3e-4e32-a477-6aa17d310630","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-6240","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-6240","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"TP-Link Systems Inc.","product":"Tapo C520WS v2","version":"affected 1.2.6 Build 260528 custom","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":{"cve_year":"2026","cve_id":"6240","cve":"CVE-2026-6240","epss":"0.000220000","percentile":"0.063830000","score_date":"2026-06-14","updated_at":"2026-06-15 00:14:09"},"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"adp":[{"metrics":[{"other":{"content":{"id":"CVE-2026-6240","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","timestamp":"2026-06-08T13:07:55.306567Z","version":"2.0.3"},"type":"ssvc"}}],"providerMetadata":{"dateUpdated":"2026-06-08T13:08:05.175Z","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":"<p>A stack-based buffer overflow vulnerability exists in Tapo C520WS v2 in the ONVIF DeleteUsers service, due to insufficient boundary checks when handling multiple user deletion parameters. An authenticated attacker can send a  crafted malicious request containing an excessive number of identifiers to overflow stack memory.\n<br>Successful exploitation may result in a service crash or deadlock, leading to DoS affecting device management and monitoring functionality.&nbsp;<br></p>"}],"value":"A stack-based buffer overflow vulnerability exists in Tapo C520WS v2 in the ONVIF DeleteUsers service, due to insufficient boundary checks when handling multiple user deletion parameters. An authenticated attacker can send a  crafted malicious request containing an excessive number of identifiers to overflow stack memory.\n\nSuccessful exploitation may result in a service crash or deadlock, leading to DoS affecting device management and monitoring functionality."}],"impacts":[{"capecId":"CAPEC-100","descriptions":[{"lang":"en","value":"CAPEC-100 Overflow Buffers"}]}],"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-121","description":"CWE-121 Stack-based buffer overflow","lang":"en","type":"CWE"}]}],"providerMetadata":{"dateUpdated":"2026-06-05T23:51:39.483Z","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 Stack-based Buffer Overflow in ONVIF DeleteUsers Service on TP-Link Tapo C520WS","x_generator":{"engine":"Vulnogram 1.0.1"}}},"cveMetadata":{"assignerOrgId":"f23511db-6c3e-4e32-a477-6aa17d310630","assignerShortName":"TPLink","cveId":"CVE-2026-6240","datePublished":"2026-06-05T23:51:39.483Z","dateReserved":"2026-04-13T17:10:23.938Z","dateUpdated":"2026-06-08T13:08:05.175Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-06-06 00:16:41","lastModifiedDate":"2026-06-08 15:01:06","problem_types":["CWE-121","CWE-121 CWE-121 Stack-based buffer overflow"],"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"}}]},"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"6240","Ordinal":"1","Title":"Authenticated Stack-based Buffer Overflow in ONVIF DeleteUsers S","CVE":"CVE-2026-6240","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"6240","Ordinal":"1","NoteData":"A stack-based buffer overflow vulnerability exists in Tapo C520WS v2 in the ONVIF DeleteUsers service, due to insufficient boundary checks when handling multiple user deletion parameters. An authenticated attacker can send a  crafted malicious request containing an excessive number of identifiers to overflow stack memory.\n\nSuccessful exploitation may result in a service crash or deadlock, leading to DoS affecting device management and monitoring functionality.","Type":"Description","Title":"Authenticated Stack-based Buffer Overflow in ONVIF DeleteUsers S"}]}}}