[$] Emacs code completion can cause compromise

Emacs has had a
few bugs related to accidentally
permitting the execution of untrusted code. Unfortunately, it seems as though
another bug of that sort has appeared — and may be harder to patch,
because the problem comes from the way Emacs handles expansion of Lisp macros in
code being analyzed. The
vulnerability is only practically exploitable in a non-default configuration, so
not every Emacs user has something to worry about. The Emacs
developers are reportedly working on a fix, but have not yet shared details
about it. In the meantime, every Emacs version since at least
26.1 (released in May 2018) through the current development version is vulnerable.