This is so cool! If the bug originates in dvips code then it's probably decades old. Confession: About a couple of years ago I tried running AFL (as the author

This is so cool! If the bug originates in dvips code then it's probably decades old. Confession: About a couple of years ago I tried running AFL (as the author here did) on tex, but got nowhere; couldn't even get it to get to the interesting parts. (Took ages even figuring out how to compile TeX.) Good call starting with dvips which works with binary formats... and really cool exploitation here. There is a lot of code in a TeX distribution: there's the “core” code written by Knuth in WEB, and then there's (probably orders of magnitude larger) all the code of LaTeX (and other) macro packages (written “in TeX”), which are both quite likely harmless. But there's also a lot of other code that gets much less attention... from everything that's been written for TeX (and its extensions) to interface with the system, to common utilities, etc.