An anonymous reader writes "Satellite Communications (SATCOM) play a vital role in the global telecommunications system, but the security of the devices used leaves much to be desired. The list of security weaknesses IOActive found while analyzing and reverse-engineering firmware used on the most widely deployed Inmarsat and Iridium SATCOM terminals does not include only design flaws but also features in the devices themselves that could be of use to attackers. The uncovered vulnerabilities include multiple backdoors, hardcoded credentials, undocumented and/or insecure protocols, and weak encryption algorithms. These vulnerabilities allow remote, unauthenticated attackers to compromise the affected products. In certain cases no user interaction is required to exploit the vulnerability; just sending a simple SMS or specially crafted message from one ship to another ship would be successful for some of the SATCOM systems."