# CVE-2026-6239: TP-Link Tapo C520WS stack buffer overflow in ONVIF CreateUsers service

Source: https://junglewise.ai/threats/cve-2026-6239-tp-link-tapo-c520ws-stack-buffer-overflow-in-onvif-createusers  
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-2026-6239 · Severity: info · CVSS 6.8 · Published 2026-06-06

The TP-Link Tapo C520WS is an outdoor security camera. A vulnerability in its user management service allows an authorized user to crash the device's management functions by sending a specially crafted request. This results in a denial-of-service condition, preventing the camera from being configured or managed until the service is restored.

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-2026-6239 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-6239 being exploited in the wild.

**How severe is CVE-2026-6239?** 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-2026-6239?** 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-2026-6239 attacked?** It is attacked from the adjacent network, in a network appliance.

**Am I affected by CVE-2026-6239?** 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 CreateUsers service of the TP-Link Tapo C520WS v2. The vulnerability is caused by a failure to properly validate the number of XML user nodes during request processing. An authenticated attacker with high privileges can exploit this by sending a specially crafted ONVIF request containing an excessive number of user entries. This triggers memory corruption, leading to the unexpected termination of the ONVIF management service and a subsequent denial-of-service (DoS) affecting device configuration and management. The attack vector is classified as 'Adjacent' (AV:A) per the vendor's CVSS 4.0 string.

## Affected products

- TP-Link Tapo C520WS v2

## Timeline

- 2026-06-05: advisory: NVD and TP-Link published advisory details.
- 2026-06-06: disclosed

## 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 overflow in ONVIF DeleteUsers service](https://junglewise.ai/threats/cve-2026-6240-tp-link-tapo-c520ws-stack-overflow-in-onvif-deleteusers-service)
- [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)