As I posted earlier the particular link to Slacko5.7 updated has all the Slackware updates to March 2017, and the FireFox thats installed is more secure than default. I cannot, and will not speak for other distros made by other people.
As to the apparent X11 / x boot-up problem, that is patched in the particular Slacko5.7, as is the nasty one that borks the Puppy completely. After March, cheeck in at slackware as others have suggested. I do go there and warn others if an update forgets to clean-up after itself, or gets wonky. In some cases like doing an Openssl update, or X11, or the nasty update, I'd be inclined to remaster the whole Pup, and toss the old one.
JMHO
8Geee
