Executive brief
A vulnerability exists in the Tenda AC8V4 wireless router, a device used to provide home and small office internet connectivity. An attacker can send a specially crafted web request to the router's configuration interface to cause the device to crash or become unresponsive. This could lead to a loss of internet connectivity for all connected users and may require a manual restart of the hardware to restore service.
Technical details
A stack-based buffer overflow (CWE-121) exists in the Tenda AC8V4 router firmware version V16.03.34.06. The vulnerability is located within the 'form_fast_setting_wifi_set' function at the '/goform/fast_setting_wifi_set' endpoint. The application retrieves the 'timeZone' parameter from a POST request and processes it using the 'strcpy' function without performing adequate length validation. By providing a sufficiently long string in the 'timeZone' field, an unauthenticated remote attacker can overwrite the stack, leading to a denial-of-service (DoS) condition. Successful exploitation requires bypassing a check on the 'ssid' parameter to reach the vulnerable code path at address 0x044DB3C.
Affected products
- Tenda AC8V4 V16.03.34.06
Timeline
- 2025-07-24: disclosed: Initial disclosure and NVD publication