CVE-2025-3666: Totolink a3700r Firmware

Medium severity, CVSS 5.3. EPSS: 0.6% chance of exploitation in the next 30 days.

A vulnerability was found in TOTOLINK A3700R 9.1.2u.5822_B20200513 and classified as critical. Affected by this issue is the function setDdnsCfg of the file /cgi-bin/cstecgi.cgi. The manipulation leads to improper access controls. The attack may be launched remotely. The exploit has been disclosed to the public and may be used. The vendor was contacted early about this disclosure but did not respond in any way.

Affected products

• Totolink a3700r Firmware: version 9.1.2u.5822_b20200513 only

Published 2025-04-16. Last modified 2026-06-17.