For quite some time we have been seeing espionage cases reaching countries, governments and large companies. A large number of backdoors were found on network devices, mobile phones and other related devices, having as main cases the ones that were reported by the media, such as: TP- Link, Dlink, Linksys, Samsung and other companies which are internationally renowned. This article will discuss a backdoor found on the modem / router XXX, equipment that has a big question mark on top of it, because there isn't a vendor identification and no information about who's its manufacturer and there are at least 7 companies linked to its production, sales and distribution in the market. Moreover, some of them never really existed. Which lead us to question on the research title: Who put the backdoor in my modem?? Degree in Computer Science from Fumec University, Security Analyst and Researcher at Ibliss Seguranca & Inteligencia. Certified by Offesinve Security(OSCP) and Elearn(WPT) as Pentester, Ewerson has published articles in the Brazilian Information Security/Computers magazines H4ck3r and GEEK, moreover, posted exploits and advisory on SecurityFocus found in big companies like: IBM, McAfee, Skype, Technicolor, Tufin, TrendMicro and others. Contrib to develop some modules to Metasploit Framework Project. Founder of BHack Conference and Area31, the first hackerpsace in Minas Gerais. Was speaker at: Defcon Bangalore - India - On the subject: Steganography QRcodes using RGB subtle pixel color mutation - 2013 Anna University, Chennai - India - On the subject: Hacking Citrix Servers - 2013 Inside 3d Printing - FabScan / 3D Scan - 2014 Bsides Brazil - In the topic: Hacking Citrix Servers - 2013 Bsides Brazil - On the subject: From bug to Metasploit module. 2012 Just4Meeting 3.0. Portugal - On the subject: From bug to Metasploit module. 2012