# CVE-2026-36815: Tenda W15E buffer overflow in formSetNetCheckTools

Source: https://junglewise.ai/threats/cve-2026-36815-tenda-w15e-buffer-overflow-in-formsetnetchecktools  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-06-09. Updated: 2026-06-09  
License: CC BY 4.0 with a link back

CVE-2026-36815 · Severity: info · CVSS 7.5 · Published 2026-06-09

The Tenda W15E enterprise router is susceptible to a security flaw that can be triggered by sending a specifically formatted web request. An attacker can exploit this to crash the device's management service or cause the entire router to become unstable. This results in a denial of service, preventing legitimate users from accessing the network or managing the device.

Technologies: [Tenda W15E](https://junglewise.ai/threats/technologies/w15e). Vendors: [Tenda](https://junglewise.ai/threats/vendors/tenda).

## Quick answers

**Is CVE-2026-36815 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-36815 being exploited in the wild.

**How severe is CVE-2026-36815?** Informational severity, with a CVSS score of 7.5, published 9 June 2026.

**Which products and versions are affected?** Tenda W15E v15.11.0.10.

**Is there a fix for CVE-2026-36815?** 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-2026-36815 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2026-36815?** Check whether you run Tenda W15E 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 buffer overflow vulnerability exists in the Tenda W15E router (v15.11.0.10) within the 'formSetNetCheckTools' function, which is registered to the 'setFixTools' action. The root cause is an unsafe memory operation where the 'hostname' parameter, retrieved via 'websGetVar', is copied into a fixed-size buffer using 'strncpy' with a length ('__n') derived directly from the user-supplied string's length ('strlen'). Because the destination buffer size is not validated against the source length, an attacker can provide an overly long hostname (e.g., 888+ characters) to overwrite adjacent memory. This can be triggered via a network-reachable HTTP request without specific authentication mentioned, leading to a process crash or device instability (Denial of Service).

## Affected products

- Tenda W15E v15.11.0.10

## Timeline

- 2026-03-18: other: CVE request submitted to MITRE
- 2026-06-06: disclosed: Public disclosure
- 2026-06-09: advisory: NVD publication date

## References

- [https://github.com/xhh0124/SemVulLLM/tree/main/W15E/formSetNetCheckTools](https://github.com/xhh0124/SemVulLLM/tree/main/W15E/formSetNetCheckTools)

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