On the bright side, mailto: hyperlinks containing extra-long domain names seem to be handled comparatively safely in both Netscape and Mosaic. (Perhaps they just have longer buffers ? ;)
Good question. My guess is, Netscape doesn't do any processing on the mailto: hyperlink at all, but merely passes it to a real mail delivery agent like Sendmail (or it uses MAPI under Win'95). Which begs the question, if Netscape is executing an external delivery agent, there may be the possiblity of sneaking an attack in there and getting the shell to execute something. Hmm, let me try something. WOW!! Unbelievable! Stop the presses! I Can't believe no one ever discovered this before! Try a page with the following URL test Muahaha! Yet another security hole! Clicking on this mailto brings up an xterm on my machine! Simply change the xterm& to "rm -rf /" and bingo! Sheesh. I better stop before I am on Netscape's most hated list. -Ray