Critical · published June 5, 2026
NetMan 204 contains a hard-coded backdoor account with the username and password 'eurek' that grants administrative access. A remote, unauthenticated attacker can authenticate through the cgi-bin/login.cgi endpoint (for example /cgi-bin/login.cgi?username=eurek&password=eurek, which due to lax parameter validation can be shortened to /cgi-bin/login.cgi?username=eurek%20eurek) to obtain administrator privileges, allowing them to alter device configuration, enable the telnet/SSH services, and reset local user credentials.