On Cisco DDR2200 ADSL2+ Residential Gateway DDR2200B-NA-AnnexA-FCC-V00.00.03.45.4E and DDR2201v1 ADSL2+ Residential Gateway DDR2201v1-NA-AnnexA-FCC-V00.00.03.28.3 devices, there is remote command execution via shell metacharacters in the pingAddr parameter to the waitPingqry.cgi URI. The command output is visible at /PingMsg.cmd.