Craven or inept?
Wait! This is a both/and situation!
The attackers spoofed the e-mail to make it appear to come from a “web master” at Beyond.com, a job-seeking and recruiting site. Inside the e-mail, there was just one line of text: “I forward this file to you for review. Please open and view it.” This was apparently enough to get the intruders the keys to RSAs kingdom.
Details of the RSA Hack - Schneier on Security