Executive brief
A vulnerability exists in the Tenda O3v3 outdoor access point, a device used to provide long-range wireless networking. By sending a specially crafted web request to the device's management interface, an attacker can cause the system to crash or reboot. This results in a denial of service, disrupting internet connectivity and network operations for all connected users.
Technical details
A stack-based buffer overflow exists in the 'formSetCfm' CGI handler of Tenda O3v3 firmware version v1.0.0.5. The vulnerability is located within the 'save_list_data' function, where a user-controlled parameter (funcpara1) is passed to 'sprintf' without adequate length validation. Specifically, the 'acStack_154' buffer is overflowed when 'sprintf' constructs a string using the tainted input. An unauthenticated remote attacker can trigger this by sending an HTTP request with 'funcname' set to 'save_list_data' and an oversized 'funcpara1' value. While primarily identified as a Denial of Service (DoS) vector, stack overflows in this context may potentially allow for arbitrary code execution.
Affected products
- Tenda O3v3 v1.0.0.5
Timeline
- 2026-03-15: other: CVE request submitted to MITRE
- 2026-06-06: disclosed: Public disclosure of vulnerability details
- 2026-06-09: advisory: NVD published CVE-2026-36791