Critical flaws are built into phones sold by the four major U.S. cellphone carriers according to research funded by the Department of Homeland Security (DHS). The flaws allow a hacker to gain access to data, emails, text messages, and "escalate privileges and take over the device" according to Vincent Sritapan a program manager at DHS. Government officials and users outside the U.S. are vulnerable also. The vulnerabilities are built into devices before a customer purchases the phone. Researchers said it is not clear if hackers have exploited the loophole yet. "This is something that can target individuals without their knowledge," Angelos Stavrou, the founder of Kryptowire told Fifth Domain.