CVE-2025-12240: Totolink a3300r Firmware

Critical severity, CVSS 9.8. EPSS: 0.8% chance of exploitation in the next 30 days.

A security vulnerability has been detected in TOTOLINK A3300R 17.0.0cu.557_B20221024. This affects the function setDmzCfg of the file /cgi-bin/cstecgi.cgi. The manipulation of the argument ip leads to buffer overflow. It is possible to initiate the attack remotely. The exploit has been disclosed publicly and may be used.

Affected products

• Totolink a3300r Firmware: version 17.0.0cu.557_b20221024 only

Published 2025-10-27. Last modified 2026-10-08.