A stack-based buffer overflow exists in the formSetCfm function of Tenda AC6 firmware 15.03.05.16_multi, triggered by overflowing the funcname, funcpara1, and funcpara2 parameters. The overflow can corrupt memory and potentially allow an attacker to execute arbitrary code, crash the device, or tamper with its configuration. This weakness is identified as CWE-120 (Buffer Overflow) and CWE-787 (Out-of-Bounds Write).

The vulnerability affects Tenda AC6 routers that are running firmware version 15.03.05.16_multi. These consumer Wi‑Fi access points are typically managed through a web or other remote interface.

The CVSS v3.1 score of 7.5 indicates high severity, while the EPSS score of less than 1% suggests a low current probability of exploitation. This issue is not listed in the CISA KEV catalog. Based on the description, the likely attack vector is remote access to the router’s web or management interface, possibly from the local network or an external source if the interface is exposed. No active exploitation code has been publicly reported, but the theoretical impact warrants prompt action.