I wouldn't call the above URL crafted in any special way as it was a bounced SPAM mail to the postmaster, but I believe it could, in theory, be done. Basically Pine consumed 300 MB of memory upon viewing this message. It increases slowly and seems to be due to the HTML rendering code. I've sent this to the PINE maintainers but haven't had a reply. The only way out is to have another console kill it.
This is fixed in pine 4.21.