Whitelist Validation Bypass in TP-Link Tapo C520WS

On Tapo

C520WS v2, restricted accounts (for example, hub users) are intended to execute

only a limited set of low‑sensitivity operations. Due to a logic flaw in the

device’s API authorization mechanism, an attacker can craft requests that

leverage legitimate “method mapping” behavior to bypass whitelist restrictions,

allowing restricted operations to be masked as permitted requests and executed.

Successful

exploitation may allow an attacker (with access to a restricted account) to

execute unauthorized sensitive operations.

Depending on the operation invoked, impact could include device

resets, unintended configuration changes, or disruption of normal operation,

leading to loss of availability and integrity of the device.