From Wsms

Note: This page should be titled flasm (all lowercase). It is Flasm due to technical limitations of Mediawiki.

flasm is a command-line utility for assembling and disassembling swf files.

Common usage

Decompile a swf file:

[ggeller@arthur ~]$ flasm -d make-folders.swf >  make-folders.flm

see also

man flasm
http://osflash.org/
The #osflash channel on freenode.net