Executive brief
A security vulnerability exists in the Tenda TX9 Pro router, a device used to provide wireless internet connectivity. An attacker can exploit this flaw by sending a specially crafted web request to the router's management interface. If successful, this could cause the router to crash or allow the attacker to take control of the device, potentially leading to unauthorized access to network traffic or a complete loss of internet service.
Technical details
A stack-based buffer overflow vulnerability exists in the 'httpd' binary of Tenda TX9 Pro firmware version V22.03.02.20. The flaw is located within the 'sub_42EEE0' function, which handles requests to the '/goform/SetStaticRouteCfg' endpoint. The vulnerability is triggered when the 'list' POST parameter is processed using an unsafe 'sscanf' call with the format string '%[^,],%[^,],%[^,],%s'. Because the function does not validate the length of the input string before copying it into fixed-size stack buffers (v16, v18, v19, and v20), a remote attacker can provide an oversized 'list' parameter to overwrite the stack, potentially leading to arbitrary code execution or a crash of the web service.
Affected products
- Tenda TX9 Pro V22.03.02.20
Timeline
- 2024-10-21: disclosed: Initial researcher disclosure on Gitee
- 2026-07-20: advisory: CVE published to NVD dataset