# CVE-2026-9480: Edimax EW-7438RPn stack overflow in formrefresh

Source: https://junglewise.ai/threats/cve-2026-9480-edimax-ew-7438rpn-stack-overflow-in-formrefresh  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-05-25. Updated: 2026-05-26  
License: CC BY 4.0 with a link back

CVE-2026-9480 · Severity: high · CVSS 8.8 · Published 2026-05-25

A security vulnerability exists in the Edimax EW-7438RPn Wi-Fi extender, a device used to increase wireless network coverage. An attacker can send a specially crafted web request to the device to cause it to crash or potentially take full control of the hardware. This could lead to a total loss of internet connectivity through the extender and allow unauthorized access to the local network.

Technologies: [Edimax EW-7438RPn](https://junglewise.ai/threats/technologies/ew-7438rpn). Vendors: [Edimax](https://junglewise.ai/threats/vendors/edimax).

## Quick answers

**Is CVE-2026-9480 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-9480 being exploited in the wild.

**How severe is CVE-2026-9480?** High severity, with a CVSS score of 8.8, published 25 May 2026.

**Which products and versions are affected?** Edimax EW-7438RPn 1.31.

**Is there a fix for CVE-2026-9480?** 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-2026-9480 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2026-9480?** Check whether you run Edimax EW-7438RPn 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 'webs' binary of the Edimax EW-7438RPn firmware version 1.31. The vulnerability is located in the 'formrefresh' function within the '/goform/formrefresh' endpoint. The 'submit-url' POST parameter is copied into a local stack buffer without adequate bounds checking, allowing an attacker to overwrite the function's return address. Exploitation requires network reachability and basic authentication (PR:L). Successful exploitation can lead to remote code execution (RCE) or a persistent denial of service (DoS) by crashing the device's web server. As of the advisory date, the vendor has not responded to disclosure attempts.

## Affected products

- Edimax EW-7438RPn 1.31

## Timeline

- 2026-05-25: advisory: Vulnerability disclosed via VulDB and NVD
- 2026-05-25: disclosed: Public PoC released on GitHub

## References

- [https://github.com/wudipjq/my_vuln/blob/main/Edimax/vuln_18/18.md](https://github.com/wudipjq/my_vuln/blob/main/Edimax/vuln_18/18.md)
- [https://vuldb.com/submit/813902](https://vuldb.com/submit/813902)
- [https://vuldb.com/vuln/365461](https://vuldb.com/vuln/365461)
- [https://vuldb.com/vuln/365461/cti](https://vuldb.com/vuln/365461/cti)

## Related threats

- [Edimax EW-7438RPn stack overflow in formSDHCP](https://junglewise.ai/threats/cve-2026-9482-edimax-ew-7438rpn-stack-overflow-in-formsdhcp)
- [Edimax EW-7438RPn stack overflow in formStats](https://junglewise.ai/threats/cve-2026-9481-edimax-ew-7438rpn-stack-overflow-in-formstats)
- [Edimax EW-7438RPn stack overflow in formLogout](https://junglewise.ai/threats/cve-2026-9479-edimax-ew-7438rpn-stack-overflow-in-formlogout)
- [Edimax EW-7438RPn stack overflow in formLicence](https://junglewise.ai/threats/cve-2026-9463-edimax-ew-7438rpn-stack-overflow-in-formlicence)
- [Edimax EW-7438RPn stack overflow in formWpsProxyEnable](https://junglewise.ai/threats/cve-2026-9462-edimax-ew-7438rpn-stack-overflow-in-formwpsproxyenable)