%0 Electronic Article %A William J. Buchanan %A Scott Helme %A Alan Woodward %K security policies enforcement %K man-in-the-middle attacks %K HTTP strict transport security %K content security policy %K Websites %K HTTP responses %K public key pinning extension %K Web-based systems %K security header adoption %K Let Encrypt digital certificates %K code injection %K HTTP header field X-frame-options %X With the increase in the number of threats within web-based systems, a more integrated approach is required to ensure the enforcement of security policies from the server to the client. These policies aim to stop man-in-the-middle attacks, code injection, and so on. This study analyses some of the newest security options used within HTTP responses, and scans the Alexa Top 1 Million sites for their implementation within HTTP responses. These options scanned for include: content security policy, public key pinning extension for HTTP, HTTP strict transport security, and HTTP header field X-frame-options, in order to understand the impact that these options have on the most popular websites. The results show that, while the implementation of the parameters is increasing, it is still not implemented on many of the top sites. Along with this, the study shows the profile of adoption of Let's Encrypt digital certificates across the one million sites, along with a way of assessing the quality of the security headers. %@ 1751-8709 %T Analysis of the adoption of security headers in HTTP %B IET Information Security %D March 2018 %V 12 %N 2 %P 118-126 %I Institution of Engineering and Technology %U https://digital-library.theiet.org/;jsessionid=98glxboaqftw.x-iet-live-01content/journals/10.1049/iet-ifs.2016.0621 %G EN