Downloads listed here are for officially verified releases. If you're not sure which you need, you probably need the 32-bit version 3.x ISO. Alternate ISOs, including daily snapshots, are available here.

N.B. - Always compare the MD5 checksum for an ISO after you download it and before using it to make a bootable media, etc.

Version File Name Size Date Checksum
3.3.3 64-bit bccd-3.3.3.amd64.iso 722 MB January 31, 2015 (md5)
3.3.3 32-bit bccd-3.3.3.i386.iso 640 MB January 31, 2015 (md5)
3.3.2 64-bit (vulnerable to CVE 2015-0235) bccd-3.3.2.amd64.iso 722 MB December 21, 2014 (md5)
3.3.2 32-bit (vulnerable to CVE 2015-0235) bccd-3.3.2.i386.iso 640 MB December 21, 2014 (md5)

You may also want to download the script for making bootable USB under Linux.