Comment by unsnap_biceps

https://news.ycombinator.com/item?id=50234254

    OP confirmed that the server was initially serving only an index.html. In that configuration, the vulnerable code path is never reached — it requires a .php file.
    OP added php-version.php roughly 18–19 hours into the experiment (I'm not sure of the exact timing), so that period should be subtracted from the publicly displayed challenge duration.