Debian Linux is one of the Servers that was reported as being a victim of these oddities.
This link discusses the problems some of us have experienced but with the more theme, not Boost. But looks like Boost is just as vunerable in certain servers.
https://moodle.org/mod/forum/discuss.php?d=355139#p1433886
And the Moodle Tracker MDL-59188 is where it was reported.
Hope this helps?
Mary