The security vulnerability in question could be briefly summarized as,
"Fortran divide-by-zero gives root." I think that was just a specific
manifestation of the underlying problem, though. More specifically it
was actually due to failure to sanitize state after handling a SIGFPE
(and possibly other signals as well?).

I have a distinct memory of this, but can no longer find any evidence
for it. Did I just make it up from whole cloth, or was this actually a
thing?

        - Dan C.