# CVE-2026-6240: TP-Link Tapo C520WS stack overflow in ONVIF DeleteUsers service

Source: https://junglewise.ai/threats/cve-2026-6240-tp-link-tapo-c520ws-stack-overflow-in-onvif-deleteusers-service  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-06-06. Updated: 2026-06-06  
License: CC BY 4.0 with a link back

CVE-2026-6240 · Severity: info · CVSS 6.8 · Published 2026-06-06

A security vulnerability exists in the TP-Link Tapo C520WS security camera, a device used for home and business monitoring. An authorized user can cause the camera's management software to crash or freeze by sending a specially crafted request to delete users. This results in a denial-of-service, preventing owners from managing the device or viewing monitoring feeds until the system is recovered.

Technologies: [TP-Link Tapo C520WS](https://junglewise.ai/threats/technologies/tapo-c520ws). Vendors: [TP-Link](https://junglewise.ai/threats/vendors/tp-link).

## Quick answers

**Is CVE-2026-6240 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-6240 being exploited in the wild.

**How severe is CVE-2026-6240?** Informational severity, with a CVSS score of 6.8, published 6 June 2026.

**Which products and versions are affected?** TP-Link Tapo C520WS v2.

**Is there a fix for CVE-2026-6240?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-6240 attacked?** It is attacked from the adjacent network, in a network appliance.

**Am I affected by CVE-2026-6240?** Check whether you run TP-Link Tapo C520WS at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A stack-based buffer overflow (CWE-121) exists in the ONVIF DeleteUsers service of the TP-Link Tapo C520WS v2. The vulnerability is caused by insufficient boundary checks when the service handles multiple user deletion parameters. An authenticated attacker with high privileges can exploit this by sending a crafted ONVIF request containing an excessive number of identifiers. Successful exploitation leads to memory corruption, resulting in a service crash or deadlock (Denial of Service). The attack vector is restricted to the adjacent network (AV:A). Firmware updates are typically available through the Tapo mobile application.

## Affected products

- TP-Link Tapo C520WS v2

## Timeline

- 2026-06-05: disclosed: Initial disclosure by TP-Link
- 2026-06-06: advisory: NVD publication date

## References

- [https://www.tp-link.com/en/support/download/tapo-c520ws/](https://www.tp-link.com/en/support/download/tapo-c520ws/)
- [https://www.tp-link.com/us/support/download/tapo-c520ws/](https://www.tp-link.com/us/support/download/tapo-c520ws/)
- [https://www.tp-link.com/us/support/faq/5120/](https://www.tp-link.com/us/support/faq/5120/)

## Related threats

- [TP-Link Tapo C520WS format string vulnerability in ONVIF Subscribe service](https://junglewise.ai/threats/cve-2026-6242-tp-link-tapo-c520ws-format-string-vulnerability-in-onvif-subscribe)
- [TP-Link Tapo C520WS format string vulnerability in ONVIF AddScopes](https://junglewise.ai/threats/cve-2026-6241-tp-link-tapo-c520ws-format-string-vulnerability-in-onvif-addscopes)
- [TP-Link Tapo C520WS stack buffer overflow in ONVIF CreateUsers service](https://junglewise.ai/threats/cve-2026-6239-tp-link-tapo-c520ws-stack-buffer-overflow-in-onvif-createusers)
- [TP-Link Tapo C520WS auth bypass in API authorization mechanism](https://junglewise.ai/threats/cve-2026-34123-tp-link-tapo-c520ws-auth-bypass-in-api-authorization-mechanism)
- [TP-Link Tapo C520WS denial of service in RTSP server](https://junglewise.ai/threats/cve-2026-8714-tp-link-tapo-c520ws-denial-of-service-in-rtsp-server)