Key Information Title: Tenda A21 V1.0.0.0 Stack-based Buffer Overflow Description: - During a security review of the Tenda A21 router firmware (version V1.0.0.0), a critical stack-based buffer overflow vulnerability was discovered in the Wi-Fi configuration endpoint . - The vulnerability resides in the function. This function retrieves user-controlled parameters (ssid) via the interface and processes them into a fixed-size stack buffer (64 bytes). Due to the use of the unsafe function without length validation, an attacker can supply an overly long SSID to overflow the stack, potentially leading to a Denial of Service (DoS) or arbitrary code execution with root privileges. Source: https://github.com/QIU-DIE/cve-nneeww/issues/5 User: hhsw34 (UID 91076) Submission Date: 02/09/2026 12:46 PM Moderation Date: 02/20/2026 03:41 PM Status: Accepted VulDB Entry: 234711 (Tenda A21 1.0.0.0 fast_setting_wifi_set form_fast_setting_wifi_set ssid stack-based overflow) Points: 20