# CVE-2026-7101: Tenda F456 buffer overflow in fromWrlclientSet

Source: https://junglewise.ai/threats/cve-2026-7101-tenda-f456-buffer-overflow-in-fromwrlclientset  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-04-27. Updated: 2026-05-28  
License: CC BY 4.0 with a link back

CVE-2026-7101 · Severity: high · CVSS 8.8 · Published 2026-04-27

A security vulnerability exists in the Tenda F456 router, a device used to provide wireless internet connectivity. An attacker can exploit this flaw by sending a specially crafted web request to the device's management interface. If successful, this could allow the attacker to crash the router, causing a service outage, or potentially take full control of the device to monitor or redirect network traffic.

Technologies: [Tenda F456](https://junglewise.ai/threats/technologies/f456), [Tenda F456 Firmware](https://junglewise.ai/threats/technologies/f456-firmware). Vendors: [Tenda](https://junglewise.ai/threats/vendors/tenda).

## Quick answers

**Is CVE-2026-7101 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-7101 being exploited in the wild.

**How severe is CVE-2026-7101?** High severity, with a CVSS score of 8.8, published 27 April 2026.

**Which products and versions are affected?** Tenda F456 1.0.0.5.

**Is there a fix for CVE-2026-7101?** 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-2026-7101 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2026-7101?** Check whether you run Tenda F456 or Tenda F456 Firmware 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 vulnerability exists in the 'httpd' component of Tenda F456 firmware version 1.0.0.5. The flaw is located within the 'fromWrlclientSet' function in the '/goform/WrlclientSet' file. The vulnerability is triggered when the function processes the user-provided 'GO' parameter; it fails to perform adequate length checks before passing the data to 'sprintf' within the 'ask_to_reboot' function. An authenticated remote attacker can exploit this by sending a POST request with an oversized 'GO' parameter, leading to a buffer overflow of the 's_1' stack buffer. This can result in a denial of service (DoS) or remote code execution (RCE). Public exploit code (PoC) has been disclosed.

## Affected products

- Tenda F456 1.0.0.5

## Timeline

- 2026-04-27: disclosed: Vulnerability disclosed and assigned CVE-2026-7101
- 2026-04-27: advisory

## References

- [https://github.com/Litengzheng/vuldb_new/blob/main/F456/vul_139/README.md](https://github.com/Litengzheng/vuldb_new/blob/main/F456/vul_139/README.md)
- [https://vuldb.com/submit/798474](https://vuldb.com/submit/798474)
- [https://vuldb.com/vuln/359676](https://vuldb.com/vuln/359676)
- [https://vuldb.com/vuln/359676/cti](https://vuldb.com/vuln/359676/cti)
- [https://www.tenda.com.cn/](https://www.tenda.com.cn/)

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