TP-Link Tapo C520WS v2 ONVIF DeleteUsers Service stack-based overflow

Summaryinfo

A vulnerability, which was classified as critical, has been found in TP-Link Tapo C520WS v2. Impacted is an unknown function of the component ONVIF DeleteUsers Service. This manipulation causes stack-based overflow. This vulnerability is registered as CVE-2026-6240. Remote exploitation of the attack is possible. No exploit is available.

Detailsinfo

A vulnerability classified as critical was found in TP-Link Tapo C520WS v2 (affected version unknown). Affected by this vulnerability is an unknown functionality of the component ONVIF DeleteUsers Service. The manipulation with an unknown input leads to a stack-based overflow vulnerability. The CWE definition for the vulnerability is CWE-121. A stack-based buffer overflow condition is a condition where the buffer being overwritten is allocated on the stack (i.e., is a local variable or, rarely, a parameter to a function). As an impact it is known to affect availability. The summary by CVE is:

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. Successful exploitation may result in a service crash or deadlock, leading to DoS affecting device management and monitoring functionality.

It is possible to read the advisory at tp-link.com. This vulnerability is known as CVE-2026-6240 since 04/13/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation requires an enhanced level of successful authentication. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 06/06/2026).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Vendor

• TP-Link

Name

• Tapo C520WS v2

License

• commercial

Website

• Vendor: https://www.tp-link.com/

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