# CVE-2026-6121: Tenda F451 stack overflow in WrlclientSet

Source: https://junglewise.ai/threats/cve-2026-6121-tenda-f451-stack-overflow-in-wrlclientset  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-04-12. Updated: 2026-05-10  
License: CC BY 4.0 with a link back

CVE-2026-6121 · Severity: high · CVSS 8.8 · Published 2026-04-12

A security vulnerability has been identified in the Tenda F451 wireless router. This device is commonly used to provide internet connectivity and local networking for homes and small offices. An attacker could exploit this flaw to crash the router or potentially take full control of the device, which could lead to the interception of network traffic or unauthorized access to the local network.

Technologies: [Tenda F451](https://junglewise.ai/threats/technologies/f451), [Tenda F451 Firmware](https://junglewise.ai/threats/technologies/f451-firmware). Vendors: [Tenda](https://junglewise.ai/threats/vendors/tenda).

## Quick answers

**Is CVE-2026-6121 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-6121 being exploited in the wild.

**How severe is CVE-2026-6121?** High severity, with a CVSS score of 8.8, published 12 April 2026.

**Which products and versions are affected?** Tenda F451 firmware 1.0.0.7.

**Is there a fix for CVE-2026-6121?** 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-2026-6121 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2026-6121?** Check whether you run Tenda F451 or Tenda F451 Firmware. 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 vulnerability exists in the httpd component of Tenda F451 firmware version 1.0.0.7. The flaw is located within the WrlclientSet function in the /goform/WrlclientSet handler. By manipulating the 'GO' argument in a crafted HTTP request, a remote attacker with low privileges can trigger the overflow. This can lead to arbitrary code execution or a crash of the web service (Denial of Service). Public exploit code is reportedly available, increasing the risk of exploitation.

## Affected products

- Tenda F451 firmware 1.0.0.7

## Timeline

- 2026-04-12: disclosed: Initial vulnerability report published

## References

- [https://github.com/Jimi-Lab/cve/issues/12](https://github.com/Jimi-Lab/cve/issues/12)
- [https://vuldb.com/submit/792865](https://vuldb.com/submit/792865)
- [https://vuldb.com/vuln/356984](https://vuldb.com/vuln/356984)
- [https://vuldb.com/vuln/356984/cti](https://vuldb.com/vuln/356984/cti)
- [https://www.tenda.com.cn/](https://www.tenda.com.cn/)

## Related threats

- [Tenda F451 stack-based buffer overflow in fromNatlimit](https://junglewise.ai/threats/cve-2026-11557-tenda-f451-stack-based-buffer-overflow-in-fromnatlimit)
- [Tenda F451 OS command injection in formWriteFacMac](https://junglewise.ai/threats/cve-2026-11556-tenda-f451-os-command-injection-in-formwritefacmac)
- [Tenda F451 stack buffer overflow in fromAdvSetWan](https://junglewise.ai/threats/cve-2026-6137-tenda-f451-stack-buffer-overflow-in-fromadvsetwan)
- [Tenda F451 stack-based buffer overflow in frmL7ImForm](https://junglewise.ai/threats/cve-2026-6136-tenda-f451-stack-based-buffer-overflow-in-frml7imform)
- [Tenda F451 stack overflow in SetIpBind](https://junglewise.ai/threats/cve-2026-6135-tenda-f451-stack-overflow-in-setipbind)