The first paragraph on anything with an acronym in it should explain the bloody acronym. I assumed CTF was an encryption standard, given the headline. It was only coming here and reading the comments that made me realise it's a game-format ("Capture The Flag").
Capture the flag the only expansion of CTF that i know but even if it is capture the flag this still doesnt make any sense. Like Quake CTF?
I don't know what to tell you. If you don't know what "CTF" is you're not the target of this blog post. It's like stumbling upon article "What's new in HTTP/2" and complaining that "HTTP" acronym is not explained.
I don't mean that everyone must know what CTF is, but sometimes it's OK to write things just for your community (CTF community in this case), not for general population.