Usually, information security management practices do not explicitly take account of weak signals, factors that lie below the detection surface, which may, however, constitute a huge security threat. This study analyses what kinds of weak signals are present in information security, followed by a discussion on their detection. Responses to weak signals are also considered as well as certain privacy concerns related to the issue. These issues are of great urgency not only for government officials responsible of public security and dealing with the current wave of terrorism, but also to corporate information security and top managers running the day to day business of their companies.