On 8 Apr 2019, at 16:35, Shawn Heisey via dovecot <dovecot@dovecot.org> wrote: > I would like to create a sieve rule where I do a regex match on ALL headers, > not a specific header.
This is a really bad idea. Headers can be quite long, contain data that you do not have control over, and checking all headers will be very expensive and may leave you open to various regex attacks. https://en.wikipedia.org/wiki/ReDoS I don't know if it is possible, but I certainly wouldn't do it. -- what was supposed to be so special about a full moon? It was only a big circle of light. And the dark of the moon was only darkness. But half-way between the two, when the moon was between the worlds of light and dark, when even the moon lived on the edge... maybe then a witch could believe in the moon. --Witches Abroad
