CVE-2026-34123
HighCVSS 7.0Exploitation Probability (EPSS)
Low risk5th percentile - higher than 5% of all known CVEs
Summary
Tapo C520WS v2 has a logic flaw in its API authorization mechanism. Restricted accounts can bypass whitelist restrictions and perform unauthorized operations like device reset or configuration changes.
Risk Assessment
An attacker with a restricted account can disrupt camera operation, leading to loss of availability and integrity.
Recommendation
Apply a firmware update from the vendor as soon as it becomes available.
Other vulnerabilities in Tapo C520WS
See all- CVE-2026-6242Medium
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 loss of real-time alarm functionality and disruption of event notifications.
- CVE-2026-6241Medium
Format string vulnerability in the ONVIF AddScopes function in Tapo C520WS v2. User-controlled input is improperly passed to formatting functions. An attacker can inject format specifiers, causing the ONVIF service to crash and resulting in DoS.
- CVE-2026-6240Medium
The Tapo C520WS v2 device has a stack-based buffer overflow vulnerability in the ONVIF DeleteUsers service due to insufficient boundary checks when handling multiple user deletion parameters. An authenticated attacker can send a crafted request with an excessive number of identifiers to overflow stack memory.
- CVE-2026-6239Medium
A stack-based buffer overflow vulnerability exists in Tapo C520WS v2 in the ONVIF CreateUsers service, where the device fails to properly validate the number of XML user nodes during request processing. An authenticated attacker can send a specially crafted ONVIF request containing an excessive number of user entries to trigger memory corruption.
Original NVD description (English source)
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.