--shell-escape sandboxes pdflatex to some degree. Still, it is perfectly possible for it to, for instance, open and read files, e.g. through
\input or Tex primitives such as
Is there a list of Tex primitives and LaTeX macros which, if blacklisted, will prevent pdflatex from reading or writing to files, and more generally will effectively sandbox it? I am especially interested in the case that the
xymatrix packages are used.
\def should presumably be blacklisted, as well as use of packages, and programming constructs like
On a related note, even if one does not prevent file reading, if one blacklists
/home/, and so on, is it possible to prevent pdflatex from leaving the working directory on a linux machine?