CVE-2026-34121

An authentication bypass vulnerability within the HTTP handling of the DS configuration service in TP-Link Tapo C520WS v2.6 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. Successful exploitation allows unauthenticated execution of restricted configuration actions, which may result in unauthorized modification of device state.

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector ADJACENT_NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://www.tp-link.com/en/support/download/tapo-c520ws/#Firmware-Release-Notes	Release Notes
https://www.tp-link.com/us/support/download/tapo-c520ws/#Firmware-Release-Notes	Release Notes
https://www.tp-link.com/us/support/faq/5047/	Vendor Advisory

Configurations

Configuration 1 (hide)

AND

cpe:2.3:o:tp-link:tapo_c520ws_firmware:*:*:*:*:*:*:*:*

cpe:2.3:h:tp-link:tapo_c520ws:2.6:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-04-02 18:16

Updated : 2026-07-24 21:10

NVD link : CVE-2026-34121

Mitre link : CVE-2026-34121

CVE.ORG link : CVE-2026-34121

JSON object : View

Products Affected

tp-link

tapo_c520ws
tapo_c520ws_firmware

CWE

CWE-287

Improper Authentication

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Un atacante no autenticado puede adjuntar una acci\u00f3n exenta de autenticaci\u00f3n a una solicitud que contiene acciones privilegiadas de 'DS do', omitiendo las verificaciones de autorizaci\u00f3n.\n\nLa explotaci\u00f3n exitosa permite la ejecuci\u00f3n no autenticada de acciones de configuraci\u00f3n restringidas, lo que puede resultar en una modificaci\u00f3n no autorizada del estado del dispositivo."}], "lastModified": "2026-07-24T21:10:00.143", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:tp-link:tapo_c520ws_firmware:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "710DD89A-E94F-4371-A03F-698C2F61D9C1", "versionEndExcluding": "1.2.4"}], "operator": "OR"}, {"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:h:tp-link:tapo_c520ws:2.6:*:*:*:*:*:*:*", "vulnerable": false, "matchCriteriaId": "72666951-E72F-4494-9A90-1F0B22E2F3CD"}], "operator": "OR"}], "operator": "AND"}], "sourceIdentifier": "f23511db-6c3e-4e32-a477-6aa17d310630"}