Vulnerability · Published May 4, 2026 · Assigned by VulnCheck
CVE-2026-41927WDR201A WiFi Extender Stack-Based Buffer Overflow via firewall.cgi
High 8.3
In plain English
A high-severity stack buffer overflow in WDR201A WiFi Extender from Shenzhen Yipu Commercial and Trading Co., Ltd. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 34% of all known vulnerabilities).
Official description
WDR201A WiFi Extender (HW V2.1, FW LFMZX28040922V1.02) contains a stack-based buffer overflow vulnerability in the firewall.cgi and makeRequest.cgi binaries that allows unauthenticated attackers to overwrite the saved return address by sending a POST request with a Content-Length header exceeding 512 bytes. Attackers can exploit insufficient length validation in the fgets() call to achieve arbitrary code execution through return-oriented programming or return-to-libc techniques.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Shenzhen Yipu Commercial and Trading Co., Ltd | WDR201A WiFi Extender | 0 – through 1.02.0 |
Weakness: CWE-121 · Vector: CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N
References
- https://mstreet97.github.io/security-research/iot/vulnerability-disclosure/ai-assisted-research/cybersecurity/cve/2026/05/04/Teaching_the_Machine_Where_to_Look.html technical-description, exploit
- https://www.made-in-china.com/showroom/yeapook/#:~:text=Established%20in%202015.%2CDistrict%2C%20Shenzhen%2C%20Guangdong%2C%20China product
- https://www.vulncheck.com/advisories/wdr201a-wifi-extender-stack-based-buffer-overflow-via-firewall-cgi third-party-advisory