There is a long-standing debate about which phase in the Software Development Life Cycle causes the most bugs: the specification phase or the coding phase? Along with the information on the cost to fix these bugs, answering this question would allow better allocation of QA (Quality Assurance) resources. Furthermore, the cost of bug fixes remains the subject of much debate.

A recent study by NIST shows that, in the software industry at large, coding bugs are causing the majority of security issues. They analyzed the provenance of security bugs across all publicly disclosed vulnerabilities in the National Vulnerability Database from 2008 to 2016. They discovered that coding bugs account for two thirds of the total. As they say:

The high proportion of implementation errors suggests that little progress has been made in reducing these vulnerabilities that result from simple mistakes, but also that more extensive use of static analysis tools, code reviews, and testing could lead to significant improvement.

Our view at AdaCore is that the above list of remedies lacks a critical component for "reducing these vulnerabilities that result from simple mistakes" and probably the most important one: pick a safer programming language! This might not be appropriate for all your software, but why not re-architect your system to isolate the most critical parts and progressively rewrite them with a safer programming language? Better still - design your next system this way in the first place. What safer language to choose? One candidate is Ada, or its SPARK subset. How can they help? We've collected the answers to that question in a booklet to help people and teams who want to use Ada or SPARK for increasing the security of their software. It is freely available here.