IBM Lotus Notes 6.0, 6.5, 7.0, and 8.0 signs an unsigned applet when a user forwards an email message to another user, which allows user-assisted remote attackers to bypass Execution Control List (ECL) protection.
https://euvd.enisa.europa.eu/vulnerability/EUVD-2008-0869
http://www.vupen.com/english/advisories/2008/0600/references