UK Defense Security Manual Leaked
Wow. It’s over 2,000 pages, so it’ll take time to make any sense of. According to Ross Anderson, who’s given it a quick look over, “it seems to be the bureaucratic equivalent of spaghetti code: a hodgepodge of things written by people from different backgrounds, and with different degrees of clue, in different decades.”
The computer security stuff starts at page 1,531.
EDITED TO ADD (10/6): An article.